Commodore 64 Service Manual

  *********

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The Project 64 etext of the Commodore 64 Service Manual, converted to
etext by Sami Rautiainen . This is a complete
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C64SM12.TXT, May 2002, etext #165.

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~

                                 SERVICE MANUAL
                               MODEL C64 COMPUTER

                          September 1985  PN-314001-02



                       Commodore Business Machines, Inc.
           1200 Wilson Drive, West Chester, Pennsylvania 19380 U.S.A.

                Commodore makes no expressed or implied
                warranties with regard to the information
                contained herein. The information is made
                available solely on as is basis, and the
                entire risk as to quality and accuracy is
                within the user. Commodore shall not be liable
                for any consequential or incidental damages in
                connection with the use of the information
                contained herein. The listing of any available
                replacement part herein does not constitute in
                any case a recommendation, warranty or guaranty
                as to quality or suitability of such replacement
                part. Reproduction or use without expressed
                permission, of editorial or pictorial content,
                in any matter is prohibited.

        This manual contains copyrighted and proprietary information. No part of
        this publication may be reproduced, stored in a retrieval system, or
        transmitted in any form by any means, electronic, mechanical,
        photocopying, recording or otherwise, without the prior written
        permission of Commodore Electronics Limited.

        Copyright (C) 1985 by Commodore Electronics Limited.
        All rights reserved.












~
                                  CONTENTS
                                                                       Page
    SPECIFICATIONS ..................................................     1
    PRODUCT PARTS LIST ..............................................     2
    BLOCK DIAGRAM ...................................................     3
    CIRCUIT THEORY
        POWER SUPPLY ................................................     4
        RESET LOGIC .................................................     5
        CLOCK CIRCUITS ..............................................     6
        I/O, RAM, EXPANSION LOGIC ...................................     7
        RAM CONTROL LOGIC ...........................................     8
        5 PIN VIDEO AND AUDIO OUTPUTS ...............................     9
        8 PIN VIDEO AND AUDIO OUTPUTS ...............................    10
        CASSETTE INTERFACE ..........................................    11
        KEYBOARD, JOYSTICK & PADDLE INTERFACES ......................    12
        SERIAL INTERFACE, USER PORT .................................    13
    TROUBLESHOOTING GUIDE ...........................................    14
    BOARD IDENTIFICATION ............................................    17
    PCB ASSEMBLY #326298-01
        BOARD LAYOUT ................................................    18
        PARTS LISTS ................................................. 19,20
        SCHEMATIC #326106 ........................................... 21,22
    PCB ASSEMBLY #260407-04
        BOARD LAYOUT ................................................    23
        PARTS LIST .................................................. 24,25
        MODULATOR SCHEMATIC #251025 .................................    26
        SCHEMATIC #251138 ........................................... 26,27
    PCB ASSEMBLY #250425-01
        BOARD LAYOUT ................................................    28
        PARTS LIST .................................................. 29,30
        MODULATOR SCHEMATIC #251696 .................................    31
        SCHEMATIC #251469 ........................................... 31,32
        PIN ASSIGNMENTS .............................................    33














~
                                  C64 COMPUTER

General description
                The "All Purpose" Commodore 64 us the complete computer for
                education, home or small business applications. Supported
                by quality peripherals and a full range of software, the
                Commodore 64 is perfect for the family. No other computer
                can offer such variety of uses and applications at such an
                affordable price.

Memory          64K RAM

ROM             20K ROM Standard (includes operating system and BASIC
                interpreter)

Microprocessor  6510A Microprocessor - 1.02 MHz clock
                Compatible with the 6502

Display         40 Columns X 25 lines of text

Colors          16 Background, border and character colors

Characters      Upper & lower case letters, numerals and symbols
                Reverse characters
                All PET graphic characters

Display modes   Text characters * High resolution graphics

Resolution      320 X 200 Pixels

Sprites         8 independent sprites
                Each consists of 24 X 21 pixels and up to 4 colors
                Each independently expandable horizontally and vertically
                Collision detection for sprite to sprite and data to sprite
                collisions

Sound           6581 Sound Interface Device includes 3 independent tone
                generators - each with 9 octaves
                Each voice includes programmable ADSR generator (Attack, Decay,
                Sustain, Release) and control of sawtooth, triangle, square,
                variable pulse and noise waveforms
                Full filtering capabilities with low, high and band pass
                filters
                External sound input

Keyboard        Full size typewriter style design

~
Keys            66 Keys total
                2 Cursor control keys
                4 Function keys (up to 8 user defined/programmable functions
                possible)
                Upper and lower case character set
                Graphic character set

Inputs/Outputs  User port
                Serial port
                ROM cartridge port
                2 Joystick/paddle ports
                Video port C1530 Cassette drive interface port

Features        Built-in BASIC 2.0 - over 70 commands, statements and functions
                Full screen editor

Peripherals     C1541 Disk drive
                C1530 Datasette
                MPS 801 Dot matrix printer
                MPS 802 Dot matrix printer
                MPS 803 Dot matrix printer
                DPS 1101 Daisey wheel printer
                C1520 Plotter/Printer
                C1702 Color monitor
                CM141 Color monitor

Power requirements
                120 Volts, 60 Hz













                Specifications subject to change without notice.




                                                                            1
~

                              PARTS LIST C-64

   PLEASE NOTE: Commodore part numbers are priced for reference only and do
   not indicate the availability of parts from Commodore. Industry standard
   parts (Resistors, Capacitors, Connectors) should be secured locally.
   Approved cross-references for TTL-chips, Transistors, etc. will be
   available in manual form through the Service Department in November of
   1984. Unique or non-standard part will be stocked by Commodore and are
   indicated on the parts list by a "C".

        TOP CASE ASSY
            Top Case                C 326113-01
            Keyboard                C 326166-02
            LED Plate               C 326160-01
            Nameplate               C 326161-01
            Lamp Hold Set           C 903820-03
            LED Assembly            C 1001039-01

        BOTTOM CASE ASSY
            Bottom Case             C 326114-01
            Foot, Self-Adhesive    C 950157-04
            PCB Shield Plate        C 326131-01
            PCB Insulation Sheet    C 326288-01

        ACCESSORIES
            Users Manual            C 326114-01
            Power Supply            C 950157-04
            RF Cable                C 326131-01
            Switch Box              C 326288-01
















                                                                            2
~


[Figure: C-64 Block Diagram]











































                                                                            3
~
                                                        C64 CIRCUIT THEORY

  +-------------------------------------------------------------------------+
  | There are three versions of the C64. The C64 with five pine connector   |
  | video output (326106). The C64 with an eight pin connector video output |
  | (251138), and the C64B which has improved system clock circuit design   |
  | (251469). Most circuit theory explanations will be the same for all     |
  | three versions. Refer to schematic 326106 unless noted otherwise.       |
  +-------------------------------------------------------------------------+

The Power Supply

The external power supply generates a regulated 5VDC and 9VAC. 5VDC is applied
to pins 5 and 1 of CN7 on the C64 pcb. Filtered by L5, C97, and C100 it is then
controlled by on/off switch S1. This 5VDC output supplies the microprocessor
logic.

9VAC is applied to pins 6 and 7 of CN7 on the C64 pcb. +12VDC, +5VDC CAN and
9VAC unregulated are outputs that are derived from this 9VAC supply. The 9VAC
supply is made available on pins 10 and 11 of the USER PORT CN2.


12VDC Generation

9VAC is added to 9VDC through CR6, and rectified by CR5. The unregulated DC
output is filtered by C88 and C89 then regulated at 12VDC by VR1. The regulated
output is filtered by C57 and C59. The 12VDC supplies the VIC and SID IC, and
the audio amplifiers.


+5VDC CAN Generation

9VAC is rectified by CR4. The unregulated DC output is filtered by C19, and C95
then regulated at 5VDC by VR2. The regulated output is filtered by C102 and
C103. The output called 5VDC CAN is separated and individually filtered into two
outputs called Vvid and Vc. Vvid is the 5VDC supply for video circuits, and Vc
is the 5VDC supply for the clock circuits.


9VDC Unregulated Generation

CR4 rectifies the 9VAC input. The output is 9VDC unregulated. This supply powers
the cassette motor transistor amplifier circuits, and the RF modulator on the
C64B version.


[Figure: Power Supply Circuits]                                             4
~
                                                        C64 CIRCUIT THEORY

[Figure: Reset Circuit schematic]


Reset Logic Circuits

U20 is a 556 timer configured as a one shot multivibrator. The output pulse
width is determined by the size of R34 and C24. Pulse width = 1.1 x R34 x
C24 = .5 seconds. The output on pin 9 is "high" active. The output of U8 is
"low" active. Reset initializes all the processor logic and causes the
processor to load the program counter register with the address of the
first instruction of the operating system program called the KERNAL. The
starting address is stored in locations $FFFC and $FFFD. The first
instruction is decode and executed giving KERNAL control of the computer
operations. The reset pulse occurs when turning the power on to the
computer.





























                                                                            5
~
                                                        C64 CIRCUIT THEORY

[Figure: Clock circuit schematic]


The C64 Clock Circuits.

Crystal Y1 develops a 14.31818MHz fundamental frequency clock signal. U31
is a Dual Voltage Controlled Oscillator. The output on pin 10 is a 14.31818
MHz clock signal called the color clock. R27 can be adjusted to obtain
exact output frequency. U30 is a frequency divider that outputs a 2MHz signal
on pin 6. U29 is a D flip flop which outputs a 1MHz signal on pin 9. U32 is
a Phase/Frequency Detector which compares the output of the U29 to the phase
0 clock, and outputs a dc voltage on pin 8 that is proportional to the phase
difference between the inputs. The second half of the Dual Voltage
Controller Oscillator U31 generates an 8.1818MHz clock signal called the
DOT Clock. The VIC IC divides the DOT clock by eight and outputs this as the
phase 0 clock on pin 17. The output of the Phase/Frequency Detector is
applied to the frequency control input pin 2 of U31. This causes tracking
of the dot clock and the color clock because one input, pin 4 of U32, is
the phase 0 clock which is derived from the dot clock, and the other pin 1
of U32, is derived from the color clock.


[Figure: Clock circuit (C64B) schematic]


The C64B Clock Circuits. Refer to schematic 251469

Crystal Y1 develops the fundamental 16Mhz clock signal. U31 is a Clock
Generator IC that outputs the 8.1818MHz DOT clock on pin 6, and the
14.31818 MHz color clock on pin 8.














                                                                            6
~
                                                        C64 CIRCUIT THEORY

[Figure: I/O, ROM and expansion port schematic]


I/O and ROM Address Decoding and Expansion Port.

I/O Address Decoding Logic

U17 is a Programmable logic array (PLA). The output F5 on pin 12 called I/O
goes "low" when any of the I/O devices controlled by U15 are selected. The
addresses are listed below for each device.

        VIC IC       $D000 - $D02E
        SID IC       $D400 - $D7FF
        Color Ram    $D800 - $DBFF
        CIA 1        $DC00 - $DC0F
        CIA 2        $DD00 - $DD0F
        I/O 1        $DE00 - $DEFF
        I/O 2        $DF00 - $DFFF

ROM Address Decoding.

Basic ROM resides at locations $A000 - $BFFF. The output F1 pin 17 of the
PLA U17 goes "low" when the BASIC ROM is selected. The KERNAL ROM resides
at locations $E000 - $FFFF. The output F2 pin 16 of the PLA U17 goes "low"
when the KERNAL ROM is selected. The CHARACTER GENERATOR ROM resides at
locations $D000 - $DFFF. The output F3 pin 15 of the PLA U17 goes "low"
when the Character Generator ROM is selected.

The Expansion Port Connections.

The expansion port is an extension of the microprocessor address, data, and
control bus. ROML decodes addresses $8000 - $9FFF, and ROMH decodes
addresses $E000 - $FFFF. These are outputs from the PLA used to select the
catridge inserted in the expansion port. I/O 1 input from U15 decodes
addresses $DE00 - $DEFF. I/O 2 output from U15 decodes addresses $DF00 -
$DFFF.








                                                                            7
~
                                                        C64 CIRCUIT THEORY

[Figure: RAM control logic schematic]


RAM Control Logic.

U13 and U25 are multiplexers. The address output from the microprocessor
are passed to RAM via U13 and U25 when the output Address Enable Control
(AEC) from the VIC IC is "high". When AEC is "low" the VIC IC outputs
refresh addresses on pins 24 - 31. AEC goes "low" when the system clock,
phase 2, is "low". Since all I/O decoding occurs when phase 2 is "high",
refresh is transparent to the processor.

Eight 4164 DRAMS provide 64k bytes of memory. One 2114 RAM (U6) provides
512 bytes of memory allocated for screen color data storage.






























                                                                            8
~
                                                        C64 CIRCUIT THEORY

[Figure: 5 pin video and audio schematic]


5 Pin Video and Audio Output Circuits

Pin 15 of the VIC IC is the sync/luminance output. Pin 14 is the color
output. A composite video output is created by mixing sync/luminance and
color. The composite output is applied to the RF modulator, and also passed
to the monitor connector CN5 on pin 4. The color output is not made
available on the monitor connector CN5 as on the 8 pin version, and the RF
modulator mixes audio with the composite video producing the TV RF output,
unlike the 8 pin version RF modulator which creates the composite video
output.































                                                                            9
~
                                                        C64 CIRCUIT THEORY

[Figure: 8 pin video and audio schematic]



8 Pin Video and Audio Output Circuits. Refer to schematic 21469

U19 is the Video Interface Chip (VIC). Sync (horizontal and vertical), and
luminance (video) is output on pin 15. This signal is passed to pin 2 of
the RF modulator. Color is output on pin 14, and passed to pin 3 of the
modulator. Light pen inputs are sensed by the VIC IC on pin 9. U18 is the
Sound Interface Device (SID). The audio output is on pin 27, and audio
input is on pin 26. The RF modulator mixes sync/luminance, color, and audio
out, generating a TV composite signal on pin 5. The RF modulator also
passes the VIC outputs to the monitor connector CN5. Audio out on pin 27 is
amplified by Q2, and output on pin 3 of CN5. Audio in is applied to pin 5
of CN5, then to pin 26 of the SID IC. Inputs from paddles connected to on
of the control ports are monitored by the SID IC on pins 23 and 24.



























                                                                           10
~
                                                        C64 CIRCUIT THEORY

[Figure: Cassette interface schematic]


The Cassette Interface Circuits.

U7 is a 6510 microprocessor. One of the features of the 6510 is a built in
parallel I/O port (P0-P5). P3 - P5 control most of the cassette interface
circuitry. P3 pin p6 of U7 outputs the write data signal to connector CN3
on pins E and 5. P4 is an input that senses the play switch depressed on the
cassette deck. P5 is on output that controls the cassette motor. When P5
goes "low", Q2 cuts off, CR2 regulates Vb of Q1 at 7.5 volts, this forward
biases Q1 and Q3, passing current through the cassette motor coil. U1 is a
Complex Interface Adapter (CIA). Parallel ports, serial outputs, and Timers
are standard features of the CIA. Read data enters on pins D, 4 of CN3. U1
accepts the read data signal on the FLAG input pin 24.





























                                                                           11
~
                                                        C64 CIRCUIT THEORY

[Figure: Interface control schematic]


Keyboard, Joystick, and Paddle Interface Circuits.

Keyboard Interface

U1 is a Complex Interface Adapter (CIA). Both parallel ports are used to
decode the keyswitches on the keyboard. Parallel port A signals (PA0 - PA7)
are outputs. PArallel port B signals (PB0 - PB7) are inputs. A "0" bin is
shifted through the parallel port A, when a key is depressed on the
keyboard the "0" bit is returned on one of the parallel port B inputs. A
program in the KERNAL ROM generates the shifting "0" bit output on parallel
port A, and decodes the signals returning on the parallel port B inputs.
Depressing the restore key causes U20 to trigger. U9 pin 6 goes "low"
generating a Non- Maskable Interrupt (NMI) at the processor. This causes
the processor to execute a subroutine which initializes the I/O interfaces.
If the STOP key is depressed at the same time, BASIC flags are initialized.


[Figure: Keyboard matrix]


Joystick Interface

U1 also controls the joystick. Parallel port A accepts inputs from the B
joystick connected to control port 2. Parallel port B accepts inputs from
the A joystick connected to control port 1. When the joystick is moved up,
down, left, right, or the fire button is depressed, a ground potential is
applied to the appropriate input of U1.

Paddle Interface

A Variable resistor is connected to adjusting knob on the paddle. When the
knob is rotated, the resistance varies controlling the time constant of an
RC network. The Voltage developed across the capacitor is input to an A/D
converter internal to the SID chip U18. The digital output is stored in one
of the SID registers. The paddle position can be determined by the reading
the contents of the appropriate register. U28 is a 4066 CMOS switch. The
signals from the paddles are passed to the SID chip when the Enable inputs
(E0 - E3) of U28 are "high".

NOTE: U1 port assignments are incorrect on schematics. Refer to Keyboard
      Matrix for correct assignments.
                                                                           12
~
                                                        C64 CIRCUIT THEORY

[Figure: Serial interface schematic]


The Serial Interface and User Port Circuits

The Serial Interface.

U2 is a Complex Interface Adapter (CIA). Parallel port signals PA3-PA7
control the serial bus interface. PA3 is the Attention (ATN) output. This
signal is inverted by U8 before being transmitted to a device on the bus.
PA4 is the clock output. Data transmitted from the C64 to a device on the
bus is synchronized by this clock signal. U8 inverts the output PA4. PA5 is
the data output. U8 inverts this output also. Data transmitted from a device
on the bus to the C64 is synchronized by a clock generated by the
transmitting device. The Clock signal is input on PA6. Data transmitted
from a device on the bus to the C64 is input on PA7. When a device on the
bus wants to communicate with the C64, SQR IN goes "low" indicating service
is requested.


The User Port

Parallel port B of U2 (PB0 - PB7) is made available on the user port.
Parallel data transfers with external device are made very easily through
this parallel port. SP2 and SP1 are bi-directional serial ports. CNT1 and
CNT2 are bi-directional synchronizing clock signals for each serial bus.


















                                                                           13
~
                          64 TROUBLESHOOTING GUIDE
+--------------------------------------+------------------------------------+
|          SYMPTOM                     |          POSSIBLE SOLUTION         |
+--------------------------------------+------------------------------------+
|Blank screen on power up.             |Check External Power Supply         |
|                                      |      U4 (KERNAL ROM), U17 (PLA)    |
|                                      |      U7 (6510 MPU), U3 (ROM)       |
|                                      |      U8 (7406 IC), U19 (VIC II)    |
|                                      |      U9-U12 (4164 RAM),            |
|                                      |      U21-U24 (4164 RAM)            |
|                                      |      BT2, CR4, VR1                 |
+--------------------------------------+------------------------------------+
|Out of memory error on power up.      |Check U9-U12 (4164 RAM)             |
|                                      |      U21-U24 (4164 RAM)            |
|                                      |**** USE DIAGNOSTIC TEST - DISK     |
+--------------------------------------+------------------------------------+
|No cursor displayed.                  |Check U1, U15, U7                   |
|Intermittent blank screen.            |Check U2, U7                        |
+--------------------------------------+------------------------------------+
|Powers up with graphics display and   |Check U14 (74LS258 IC)              |
|blinking cursor.                      |                                    |
+--------------------------------------+------------------------------------+
|Powers up with all the characters     |Check U26 (74LS373 IC)              |
|displayed as blocks.                  |                                    |
+--------------------------------------+------------------------------------+
|Intermittent display.                 |Check C88 (Possible Bad Connection) |
+--------------------------------------+------------------------------------+
|Powers up with the 'PRESS PLAY ON     |Check U7 (6510 MPU)                 |
|TAPE' message and the display blanks. |R1 (Possible Bad Connection)        |
+--------------------------------------+------------------------------------+
|On power up the cursor lock up.       |Check U7 (6510 MPU)                 |
|                                      |      U20 (556 IC)                  |
+--------------------------------------+------------------------------------+
|When 'RETURN' is pressed after a run  |Check U3 (ROM)                      |
|command, the cursor goes back to      |                                    |
|home position.                        |                                    |
+--------------------------------------+------------------------------------+
|Poke command does not work.           |Check U3 (ROM)                      |
+--------------------------------------+------------------------------------+
|Joystick does not operate correctly.  |Check U1, U28 (6526 CIA)            |
+--------------------------------------+------------------------------------+
|Wrong frequency.                      |Check C70                           |
+--------------------------------------+------------------------------------+
|No character lettering is displayed on|Check U3 (ROM)                      |
|the screen.                           |      U2 (CIA)                      |
+--------------------------------------+------------------------------------+
                                                                           14
~
                    64 TROUBLESHOOTING GUIDE (Continued)
+--------------------------------------+------------------------------------+
|          SYMPTOM                     |          POSSIBLE SOLUTION         |
+--------------------------------------+------------------------------------+
|Graphic characters instead of letters |Check U19 (VIC II)                  |
|displayed.                            |                                    |
+--------------------------------------+------------------------------------+
|Power up message appears but no cursor|Check U1, U15, U7 and U4            |
+--------------------------------------+------------------------------------+
|Cursor jumps to back to home position.|Check U7 (6510 MPU)                 |
+--------------------------------------+------------------------------------+
|Abnormal colors appear in the letters.|Check U6 (2114 RAM)                 |
|                                      |      U16 (4066 IC)                 |
+--------------------------------------+------------------------------------+
|Different characters are displayed and|Check RAM                           |
|cursor is locked when turned on and   |                                    |
|off.                                  |                                    |
+--------------------------------------+------------------------------------+
|System does not reset and the         |Check U20 (556 IC)                  |
|'RESTORE' key does not work.          |                                    |
+--------------------------------------+------------------------------------+
|White band scrolls down the screen.   |Check External Power Supply         |
|(60 HZ HUM)                           |      VR2 (5V Regulator)            |
+--------------------------------------+------------------------------------+
|Cursor disappears after the system    |Check U1 (6526 CIA)                 |
|warms up.                             |                                    |
+--------------------------------------+------------------------------------+
|SYNTAX ERROR displayed after system   |Check RAM, U3 (ROM)                 |
|warms up.                             |                                    |
+--------------------------------------+------------------------------------+
|Wavy screen after the system warms up.|Check External power supply         |
|                                      |      U31 (74LS629 IC)              |
|                                      |      U30 (74LS193 IC)              |
+--------------------------------------+------------------------------------+
|The system resets when it warms up.   |Check U7 (6510 MPU)                 |
|                                      |      U3 (ROM)                      |
+--------------------------------------+------------------------------------+
|Keyboard does not operate correctly   |Check U1 (6526 CIA)                 |
|when the system warms up.             |U3 (ROM)                            |
+--------------------------------------+------------------------------------+
|Black band scrolls through screen     |Check External Power Supply         |
|when the system warms up.             |      C90, C88, CR4                 |
|                                      |      VR2 (5V Regulator)            |
+--------------------------------------+------------------------------------+
|Cassette motor keeps running.         |Check U7 (6510 MPU)                 |
+--------------------------------------+------------------------------------+
                                                                           15
~
                    64 TROUBLESHOOTING GUIDE (Continued)
+--------------------------------------+------------------------------------+
|          SYMPTOM                     |          POSSIBLE SOLUTION         |
+--------------------------------------+------------------------------------+
|Cassette motor keeps running even     |Check Cassette Port for Shorts      |
|after a program is done loading. The  |      R4 (Possibly Open)            |
|TIP 29 transistor gets extremely hot  |                                    |
|and the fuse may possibly blow.       |                                    |
+--------------------------------------+------------------------------------+
|The cursor disappears when the        |Check U7 (6510 MPU)                 |
|cassette is plugged in.               |                                    |
+--------------------------------------+------------------------------------+
|Cassette runs extremely slow. The     |Check U7 (6510 MPU)                 |
|program seems to load but will not run|                                    |
+--------------------------------------+------------------------------------+
|When loading from cassette, the       |Check U20 (556 IC)                  |
|'SYNTAX ERROR' message is displayed.  |                                    |
+--------------------------------------+------------------------------------+
|DEVICE NOT PRESENT ERROR is displayed |Check U1 (6526 CIA)                 |
|when disk is used.                    |      U7 (6510 MPU)                 |
|                                      |      R28, R29, R30                 |
+--------------------------------------+------------------------------------+
|Disk drives continue to search when   |Check U2 (6526 CIA)                 |
|trying to load.                       |                                    |
+--------------------------------------+------------------------------------+
|When loading from disk and any key of |Check U20 (556 IC)                  |
|the 4th row of the keyboard is        |      R35 (Possible Bad Connection) |
|pressed, the cursor goes to home      |                                    |
|position.                             |                                    |
+--------------------------------------+------------------------------------+
|When loading from disk, a 'FILE NOT   |Check U4 (ROM)                      |
|FOUND' message is displayed.          |      U2 (6526 CIA)                 |
+--------------------------------------+------------------------------------+
|OUT OF MEMORY is displayed when disk  |Check U20 (556 IC)                  |
|is used.                              |                                    |
+--------------------------------------+------------------------------------+










                                                                           16
~
                             C64 BOARD IDENTIFICATION


            To date there are 4 version of 64 PCB assemblies in use.


VERSION         IDENTIFYING FACTORS             PCB ASSY #      SCHEMATIC #

Original        5 pin board                     326298-01       326106
                (CN5-Video port has 5 pins)

A (CR)          8 pin board                     250407-04       251138
                (CN5-Video port has 8 pins)

B               8 pin board                     250425          251469
                (Reduced oscillator circuit)

B-2             8 pin board                     250441-01*      251469


 - These boards are interchangeable with casework, keyboard, etc.; however,
   care must be taken to provide the customer with a unit that is
   compatible with their monitor and cable.

 - When component level repairs are necessary, be certain to acquire the
   appropriate part for the board you are repairing. Most modulators are
   different, as are many of the components.


* The 4th version of 64 board was recently developed and only a few may be
in the field. It is termed the 64B-2. All circuits remain the same as the
64B (Schematic 251469) with a few component location changes:

    1)  Resistors 28, 29, 30, 36, 48 were reduced to Resistor Pack RP5.

    2)  Diodes CR100-105 are no longer piggybacked. Their new locations are
        CR9, 12-16.









                                                                           17
~
                          BOARD LAYOUT #326298-01


[Figure: Board Layout #326298-01]










































                                                                           18
~
                     PARTS LIST - PCB ASSEMBLY #326298
                C - Indicates Commodore Stocked Part Numbers

  INTEGRATED CIRCUITS
U1,U2   6526 CIA                    C 906108-01
U3      2364 Basic ROM              C 901226-01
U4      2364 Kernal ROM             C 901227-03
U5      2364 Char ROM               C 901225-01
U6      2114L-30 RAM                  901453-01
U7      6510 uProcessor             C 906107-01
U8      7406                          901522-06
U9-U12  4164 (200 nS)                 901505-01
U13     74LS257                       901521-57
U14     74LS258                       901521-58
U15     74LS139                       901521-18
U16     4066                          901502-01
U17     82S100 PLA                  C 906114-01
U18     6581 SID                    C 906112-01
U19     6567 VIC II                 C 906109-04
U20     LM556                         901523-03
U21-U24 4161 (200 nS)                 901505-01
U25     74LS257                       901521-57
U26     74LS373                       901521-29
U27     74LS08                        901521-03
U28     4066                          901502-01
U29     74LS74                        901521-06
U30     74LS193                       901521-26
U31     74LS629                       901521-68
U32     MC4044                        906128-01
  TRANSISTORS
Q1      2N4401                        902652-01
Q2      2N3904                        902658-01
Q3      TIP29 B                       902653-01
Q4-8    2N2222                        902686-01
  DIODES
CR1     2.7V Zener IN4371
CR2     7.5V Zener IN755
CR3     IN914
CR4     Bridge, Varo VMO8             906129-01
CR5,6   Rectifier IN4001
  RESISTORS - All values are in ohms- 1/4W,
              5%, unless noted otherwise.
R1  3.3K        R7  10K
R2  1.5K        R8  390
R3  10K         R9  75
R4  1K          R10 120
R5  560         R11 120
~
R6  1K          R13 1K
  RESISTORS (continued)
R14 100         R30 1K
R16 1K          R31 180
R17 1.2K        R33 47K
R19 15K         R34 47K
R20 6.8K        R35 470K
R21 4.7K        R37 2.7K
R22 1.5K        R38 1K
R23 1K          R39 390
R24 3.3K        R41 1M
R25 Pot 1K      R43 3.3K
R26 75          R44 3.3K
R27 Pot 2K      R45 3.3K
R28 1K          R46 2K
R29 1K          R51 1.5K
NOTE: The input video line requires a 470 ohm,
      1/4 watt, resistor soldered to ground.

  RESISTOR PACKS
RP1,2   33, 8 Pin (Bourne No. 430BR-102-330)
RP3     33K, 8 Pin (Bourne No. 430BR-101-332)
RP4     3.3K, 10 Pin
  CAPACITORS
C1-3        Ceramic          .1 uF, 50V
C4-7        Ceramic         .47 uF, 50V, 20%
C8          Electrolytic     10 uF, 25V, +50%, -10%
C9          Ceramic         .47 uF, 50V, 20%
C10-11      Ceramic         470 pF, 50V
C12-15      Electrolytic     10 uF, 25V, +50%, -10%
C16         Ceramic          .1 uF, 50V
C17         Electrolytic     10 uF, 25V, +50%, -10%
C18         Ceramic          .1 uF, 50V
C19         Electrolytic   2200 uF, 16V
C20,21      Film            .22 uF, 100V, 20%
C22         Ceramic          .1 uF, 50V
C23         Ceramic         360 pF, 50V
C24         Electrolytic     10 uF, 25V, +50%, -10%
C25-28      Ceramic         .22 uF, 50V
C29         Ceramic         .47 uF, 50V, 20%
C30,31,32   Ceramic          .1 uF, 50V
C33         Ceramic         .47 uF, 50V, 20%
C34         Electrolytic     10 uF, 25V, +50%, -10%
C35         Ceramic          .1 uF, 50V
C36         Ceramic          20 pF, 50V
C37         Ceramic        1000 pF, 50V
                                                                           19
~
               PARTS LIST - PCB ASSEMBLY #326298 (Continued)
                C - Indicates Commodore Stocked Part Numbers

  CAPACITORS (Continued)
C38         Ceramic          51 uF, 50V
C39         Ceramic          .1 uF, 50V
C40-43      Ceramic         .22 uF, 25V, +50%, -10%
C44         Ceramic         .47 uF, 50V, 20%
C45,46,47   Ceramic          .1 uF, 50V
C48         Ceramic        1800 uF, 50V
C49         Ceramic         470 pF, 50V
C50         Ceramic         .22 uF, 50V
C51         Ceramic         .47 uF, 50V, 20%
C52,53      Ceramic         470 pF, 50V
C54         Ceramic         .22 uF, 50V
C55         Ceramic          .1 uF, 50V
C56         Ceramic          .1 uF, 50V
C57         Electrolytic     10 uF, 25V, +50%, -10%
C58         Ceramic          .1 uF, 50V
C59         Ceramic         .22 uF, 50V
C60,61      Ceramic         .47 uF, 50V, 20%
C62         Electrolytic     10 uF, 25V, +50%, -10%
C63         Ceramic         .47 uF, 50V, 20%
C64,65      Electrolytic     10 uF, 25V, +50%, -10%
C66,67      Ceramic         .47 uF, 50V, 20%
C68         Ceramic          .1 uF, 50V
C69
C70         Mica             10 pF, 500V, 5%
C71         Ceramic          .1 uF, 50V
C72         Ceramic         220 pF, 50V
C73         Ceramic         150 pF, 50V
C74         Ceramic          .1 uF, 50V
C77         Ceramic          .1 uF, 50V
C78         Ceramic         220 pF, 50V
C79         Ceramic         510 pF, 50V
C80         Ceramic          51 pF, 50V
C81         Ceramic          20 pF, 50V
C82         Ceramic          .1 uF, 50V
C83         Mica            .33 pF, 500V, 5%
C84         Ceramic          .1 uF, 50V
C85         Ceramic         .47 uF, 50V, 20%
C86         Mica             39 pF, 500V, 5%
C87         Ceramic          .1 uF, 50V
C88         Electrolytic    470 uF, 50V
C89         Ceramic          .1 uF, 50V
C90         Electrolytic    470 uF, 50V
C91         Electrolytic    100 uF, 16V
~
C92         Ceramic         .22 uF, 50V
C93         Ceramic        1800 uF, 50V

  CAPACITORS (Continued)
C94         Electrolytic     10 uF, 25V, +50%, -10%
C95,96      Ceramic          .1 uF, 50V
C97         Ceramic         .22 uF, 25V
C98,99      Ceramic          .1 uF, 50V
C100        Ceramic         .22 uF, 25V
C101        Ceramic          .1 uF, 50V
C102        Electrolytic     10 uF, 25V, +50%, -10%
C103        Ceramic          .1 uF, 50V
C105        Ceramic          .1 uF, 50V

  CONNECTORS
CN1     Header Assy 20 Pin            903331-20
CN4     6 Pin Din                   C 903361-01
CN5     5 Pin Din                   C 903362-01
CN6     44 Pin Card Edge            C 906100-02
CN7     7 Pin Din                   C 906130-01
CN8,9   Plug Assy, 8 Pin Rt. Angle  C 906126-01
CN10    Header Assy, 3 Pin

  MISCELLANEOUS
L1,2    Coil Inductor 2.2 uH          901151-17
L3      Coil Inductor 3.0 uH          901151-21
L4      Filter Line Assy            C 906127-01
L5      Coil Inductor 1.2 uH          901152-01
Y1      Crystal 14.31818 MHz        C 900558-01
SW1     Rocker Switch DPDT          C 904500-01
VR1     Voltage Regulator MC7812CT
VR2     Voltage Regulator MC7805CT
M1      Modulator                   C 326130-01
F1      Fuse, Normal Blo, 250V, 1.5A
FB1-23  Ferrite Bread                 903025-01
        Connector Panel
            (ON, OFF, Joystick)       326299-01
        Catridge Guide                326116-01
        Shield Box                  C 326265-01
        Shield Cap                  C 326267-01






                                                                           20
~
                       SCHEMATIC #326106 SHEET 1 OF 2


[Figure: Schematic #326106 sheet 1 of 2]










































                                                                           21
~
                       SCHEMATIC #326106 SHEET 2 OF 2


[Figure: Schematic #326106 sheet 2 of 2]










































                                                                           22
~
                          BOARD LAYOUT #250407-04


[Figure: Board Layout #250407-04]










































                                                                           23
~
                    PARTS LIST - PCB ASSEMBLY #250407-04
                C - Indicates Commodore Stocked Part Numbers

  INTEGRATED CIRCUITS
U1,U2   6526 CIA                    C 906108-01
U3      2364 Basic ROM              C 901226-01
U4      2364 Kernal ROM             C 901227-03
U5      2364 Char ROM               C 901225-01
U6      2114L-30 RAM                  901453-01
U7      6510 uProcessor             C 906107-01
U8      7406                          901522-06 sub:
        7416                          901522-14
U9-U12  4164 (200 nS)                 901505-01
U13     74LS257                       901521-57
U14     74LS258                       901521-58
U15     74LS139                       901521-18
U16     4066                          901502-01
U17     82S100 PLA                  C 906114-01
U18     6581 SID                    C 906112-01
U19     6567 VIC II                 C 906109-04
U20     LM556                         901523-03
U21-U24 4161 (200 nS)                 901505-01
U25     74LS257                       901521-57
U26     74LS373                       901521-29
U27     74LS08                        901521-03
U28     4066                          901502-01
U29     74LS74                        901521-06
U30     74LS193                       901521-26
U31     74LS629                       901521-68
U32     MC4044                        906128-01
  TRANSISTORS
Q1,2    2SC1815                     C 902693-01
Q3      TIP29 A                       902653-01
Q7,8    2SC1815                     C 902693-01
  DIODES
CR1     2.7V Zener IN4371             906103-02
CR2     7.5V Zener IN755              900941-01
CR4     Bridge S2VB10               C 251026-01
               DBA20B               C 251026-02
               DBA20C               C 251026-03
CR5,6   Rectifier IN4001              900750-01
  RESISTORS - All values are in ohms- 1/4W,
              5%, unless noted otherwise.
R1  3.3K        R6   1K
R2  1.5K        R7   10K
R3  10K         R16  1K
R4  1K          R17  2.7K
~
R5  560         R19  15K
  RESISTORS (continued)
R26 75          R39  390
R27 Pot 2K      R41  1M
R28 1K          R42  82
R29 1K          R43  3.3K
R30 1K          R44  3.3K
R31 180         R45  3.3K
R33 47K         R50  1M
R34 47K         R51  1.5K
R35 470K        R52  300
R36 1K          R53  390
R37 2.7K        R100 1K
R38 1K          R101 22K
  RESISTOR PACKS
RP1,2   33, 8 Pin (Bourne No. 430BR-102-330)
RP3     33K, 8 Pin (Bourne No. 430BR-101-332)
RP4     3.3K, 10 Pin
  CAPACITORS
C1-7        Ceramic          .1 uF, 25V
C8          Electrolytic     10 uF, 25V, +50%, -10%
C9          Ceramic          .1 uF, 25V
C10,11      Ceramic         470 pF, 50V
C12         Ceramic          .1 uF, 25V
C13,14,15   Electrolytic     10 uF, 25V, +50%, -10%
C16         Ceramic          .1 uF, 25V
C17         Electrolytic     10 uF, 25V, +50%, -10%
C18         Ceramic          .1 uF, 25V
C19         Electrolytic   2200 uF, 16V
C20,21      Film            .22 uF, 100V, 20%
C22         Ceramic          .1 uF, 25V
C23         Ceramic         360 pF, 50V
C24         Electrolytic     10 uF, 25V, +50%, -10%
C25-33      Ceramic          .1 uF, 25V
C34         Electrolytic     10 uF, 25V, +50%, -10%
C35         Ceramic          .1 uF, 50V
C36         Ceramic          20 pF, 50V, 5% SL
C37         Ceramic        1000 pF, 50V, 10% B
C38         Ceramic          51 uF, 50V, 5% SL
C39-47      Ceramic          .1 uF, 25V
C48         Ceramic        1800 pF, 50V, 10% B
C49-54      Ceramic          .1 uF, 25V
C55         Ceramic          .1 uF, 50V
C56         Ceramic          .1 uF, 25V
C57         Electrolytic     10 uF, 25V, +50%, -10%
C58         Ceramic          .1 uF, 50V
                                                                           24
~
              PARTS LIST - PCB ASSEMBLY #250407-04 (Continued)
                C - Indicates Commodore Stocked Part Numbers

  CAPACITORS (Continued)
C59,60      Ceramic          .1 uF, 25V
C62,65      Electrolytic     10 uF, 25V, +50%, -10%
C66,67,68   Ceramic          .1 uF, 25V
C70         Film             16 pF, 5%
C74,82      Ceramic          .1 uF, 25V
C83         Ceramic          82 pF, 5%
C84         Ceramic          .1 uF, 25V
C85         Ceramic         .47 uF, 50V, 10%
C88         Electrolytic   1000 uF, 25V
C89         Ceramic          .1 uF, 25V
C90         Electrolytic    470 uF, 50V
C91         Electrolytic    100 uF, 16V, +50%, -10%
C92         Ceramic          .1 uF, 25V
C93         Ceramic        1800 pF, 50V, 10% B
C94         Electrolytic     10 uF, 25V, +50%, -10%
C95,96      Ceramic          .1 uF, 25V
C97         Ceramic         .22 uF, 25V
C98,99      Ceramic          .1 uF, 25V, +80%, -20%
C100        Ceramic         .22 uF, 25V
C101        Ceramic          .1 uF, 50V, +80%, -20%
C102        Electrolytic     10 uF, 25V, +50%, -10%
C103        Ceramic          .1 uF, 25V
C104
C105        Ceramic          .1 uF, 25V
C108        Electrolytic     10 uF, 25V, +50%, -10%
C200        Ceramic          .1 uF, 25V

  CONNECTORS
CN1     Header Assy 20 Pin            903331-20
CN4     6 Pin Din                   C 903361-01
CN5     8 Pin Din                   C 325573-01
CN6     44 Pin Card Edge            C 906100-02
CN7     7 Pin Din                   C 251116-01
CN8,9   Plug Assy, 9 Pin MINID      C 906126-01
CN10    Header Assy, 3 Pin            903332-03

  MISCELLANEOUS
L2      Coil Inductor 2.2 uH          901151-17
L4      Coil Inductor 1.2 uH          325570-01
L5      Choke Coil                  C 325559-02
Y1      Crystal 14.31818 MHz        C 900558-01
SW1     Rocker Switch DPDT          C 904500-01
VR1     Voltage Regulator MC7812CT    901527-01
~
VR2     Voltage Regulator MC7805CT    901527-02
M1      Modulator                   C 251080-01
F1      Fuse, Normal Blo, 250V, 1.5A
FB1-23  Ferrite Bread                 903025-01
        Connector Panel
            (ON, OFF, Joystick)       251095-01
        Catridge Guide                326116-01
        Shield Box                  C 251023-01
        Shield Cap                  C 251024-01





































                                                                           25
~
                        MODULATOR SCHEMATIC #251025

[Figure: Modulator schematic #251025]





                       SCHEMATIC #251138 SHEET 1 OF 2


[Figure: Schematic #251138 sheet 1 of 2]


































                                                                           26
~
                       SCHEMATIC #251138 SHEET 2 OF 2


[Figure: Schematic #251138 sheet 2 of 2]










































                                                                           27
~
                          BOARD LAYOUT #250425-01


[Figure: Board Layout #250425-01]










































                                                                           28
~
                    PARTS LIST - PCB ASSEMBLY #250425-01
                C - Indicates Commodore Stocked Part Numbers

  INTEGRATED CIRCUITS
U1,U2   6526 CIA                    C 906108-01
U3      2364 Basic ROM              C 901226-01
U4      2364 Kernal ROM             C 901227-03
U5      2364 Char ROM               C 901225-01
U6      2114L-30 RAM                  901453-01
U7      6510 uProcessor             C 906107-01
U8      7406                          901522-06 sub:
        7416                          901522-14
U9-U12  4164 (200 nS)                 901505-01
U13     74LS257                       901521-57
U14     74LS258                       901521-58
U15     74LS139                       901521-18
U16     4066                          901502-01
U17     82S100 PLA                  C 906114-01
U18     6581 SID                    C 906112-01
U19     6567 VIC II                 C 906109-04
U20     LM556                         901523-03
U21-U24 4161 (200 nS)                 901505-01
U25     74LS257                       901521-57
U26     74LS373                       901521-29
U27     74LS08                        901521-03
U28     4066                          901502-01
U31     7701/8701                   C 251527-01
  TRANSISTORS
Q1      TIP29 A                       902653-01
Q2-4    2SC1815                     C 902693-01
  DIODES
CR1     2.7V Zener IN4371             906103-02
CR2     6.8V Zener IN755
CR4     Bridge S2VB10               C 251026-01 sub:
               DBA20B               C 251026-02 sub:
               DBA20C               C 251026-03
CR5,6   Rectifier IN4001              900750-01
CR9,              IN4148 sub:
CR12-16           IN914
CR100-105
  RESISTORS - All values are in ohms- 1/4W,
              5%, unless noted otherwise.
R1  3.3K        R26  3.3K
R2  1.5K        R31 180
R3  10K         R33 47K
R4  1K          R34 47K
R5  560         R35 470K
~
R6   1K         R37 2.7K
R7   10K        R38 1K
  RESISTORS (continued)
R39  390        R50  1M
R41  1M         R51  1.5K
R42  82         R60  100
R43  3.3K       R100 1K
R44  3.3K       R101 22K
R45  3.3K
  RESISTOR PACKS
RP1,2   33, 8 Pin (Bourne No. 430BR-102-330)
RP3     33K, 8 Pin (Bourne No. 430BR-101-332)
RP4     3.3K, 10 Pin
RP5     1K, 6 Pin
  CAPACITORS
C1-7        Ceramic          .1 uF, 25V
C9          Ceramic          .1 uF, 25V
C10,11      Ceramic         470 pF, 50V, 10%
C12         Ceramic          .1 uF, 25V
C13         Electrolytic     10 uF, 25V, +50%, -10%
C15         Tantalum        4.7 uF, 16V, 20%
C19         Electrolytic   2200 uF, 16V
C20         Film            .22 uF, 100V, 20%
C22         Ceramic          .1 uF, 25V
C23         Ceramic         360 pF, 50V, 10% sub: 390 pF
C24         Electrolytic     22 uF, 25V, +50%, -10%
C31,33,34   Ceramic          .1 uF, 25V
C37         Ceramic        1000 pF, 50V, 10% B
C38         Ceramic          51 pF, 50V, 5% SL
C39-46      Ceramic          .1 uF, 25V
C48         Ceramic        1800 pF, 50V, 10% B
C50,51,53   Ceramic          .1 uF, 25V
C59         Ceramic          .1 uF, 25V
C88         Electrolytic   1000 uF, 25V
C90         Electrolytic    470 uF, 50V
C91         Electrolytic    100 uF, 16V, +50%, -10%
C93         Ceramic        1800 pF, 50V, 10% B
C101        Ceramic          .1 uF, 50V, +80%, -20%
C102        Electrolytic     10 uF, 25V, +50%, -10%
C150-152    Ceramic         470 pF, 50V, 10%
C153        Ceramic          68 pF, 50V, 5%
C154        Ceramic         470 pF, 50V, 10%
C200        Ceramic          .1 uF, 25V
C204        Ceramic         150 pF, 50V, 10%
C205        Ceramic         220 pF, 50V, 5%
CT1         Trimmer          40 pF
                                                                           29
~
              PARTS LIST - PCB ASSEMBLY #250407-04 (Continued)
                C - Indicates Commodore Stocked Part Numbers

  CONNECTORS
CN1     Header Assy 20 Pin            903331-20
CN4     6 Pin Din                   C 903361-01
CN5     8 Pin Din                   C 325573-01
CN6     44 Pin Card Edge            C 906100-02
CN7     7 Pin Din                   C 251116-01
CN8,9   Plug Assy, 9 Pin MINID      C 251057-01
CN10    Header Assy, 3 Pin            903332-03

  MISCELLANEOUS
L2      Coil Inductor 2.2 uH          901151-17
L4      Line Filter Assy            C 251701-01
L5      Coil Inductor 1.2 uH          901152-01
Y1      Crystal 14.31818 MHz        C 251707-01
SW1     Rocker Switch DPDT          C 904500-01
VR1     Voltage Regulator MC7812CT    901527-01
VR2     Voltage Regulator MC7805CT    901527-02
M1      Modulator                   C 251696-01
        Connector Panel
            (ON, OFF, Joystick)       251095-01
        Catridge Guide                326116-01
F1      Fuse, Normal Blo, 250V, 1.5A





















                                                                           30
~
                        MODULATOR SCHEMATIC #251696

[Figure: Modulator schematic #251696]








                       SCHEMATIC #251469 SHEET 1 OF 2


[Figure: Schematic #251469 sheet 1 of 2]































                                                                           31
~
                       SCHEMATIC #251469 SHEET 2 OF 2


[Figure: Schematic #251469 sheet 2 of 2]










































                                                                           32
~
                             U1, U2 - 906108-01
                           6526 COMPLEX INTERFACE
                               ADAPTER (CIA)

          PIN               1       VSS     Ground connection
       ASSIGNMENT           2-9     PA0-PA7 Parallel port a signals.
      +----------+                          Bidirectional parallel port.
      |          |          10-17   PB0-PB7 Parallel port b signals.
  GND-+ 1      40+-CNT                      Bidirectional parallel port.
  PA0-+ 2      39+-SP       18      PC      Handshake output. A low pulse is
  PA1-+ 3      38+-RS0                      generated after a read or write
  PA2-+ 4      37+-RS1                      on port b.
  PA3-+ 5      36+-RS2      19      TOD     Time od day clock input.
  PA4-+ 6      35+-RS3                      Programmable 50hz or 60hz.
  PA5-+ 7      34+-_RES     20      VCC     5VDC input.
  PA6-+ 8      33+-DB0      21      IRQ     Interrupt output to microprocessor
  PA7-+ 9      32+-DB1                      input IRQ.
  PA0-+10      31+-DB2      22      R/W     READ/WRITE input from
  PB1-+11      20+-DB3                      microprocessor's R/W output.
  PB2-+12      29+-DB4      23      CS      Chip select input. A low pulse
  PB3-+13      28+-DB5                      will activate CIA.
  PB4-+14      27+-DB6      24      FLAG    Negative edge sensitive interrupt
  PB5-+15      26+-DB7                      input. Can be used as a handshake
  PB6-+16      25+-O2                       line for either parallel port.
  PB7-+17      24+-_FLAG    25      O2      O2 clock input. Connected to
  PPC-+18      23+-_CS                      processor common O2 clock.
  TOD-+19      22+-R/_W     26-33   DB0-DB7 Bidirectional data bus. Connects
  VCC-+20      21+-_IRQ                     to processor data bus.
      |          |          34      RES     Low active reset input.
      +----------+                          Initializes CIA.
                            35-38   RS0-RS3 Register select inputs. Used to
                                            select all internal registers
                                            for communications with the
                                            parallel ports, time of day
                                            clock and serial port (SP).
                            39      SP      Serial Port bidirectional
                                            connection. An internal shift
                                            register converts
                                            microprocessor parallel data
                                            into serial data, and vice
                                            versa.
                            40      CNT     Count input. Internal timers
                                            can count pulses applied to
                                            this input. cAn be used for
                                            frequency dependant operations.


~
                              U18 - 906112-01
                            6581 SOUND INTERFACE
                                DEVICE (SID)



          PIN               1,2,    CAP1A,1B
       ASSIGNMENT           3,4     2A,2B   Capacitor filter connections
      +----------+          5       RES     Reset input. A low pulse
      |          |                          initializes the SID.
  CAP-+1A      28+-12V      6       O2      Processor phase 2 clock input.
  CAP-+1B      27+-A.OUT    7       R/W     Processor read/write input.
  CAP-+2A      26+-EXT IN   8       CS      Chip select input.
  CAP-+2B      25+-5V       9-13    A0-A4   Address lines from processor.
 _RES-+ 5      24+-POT X    14      GND     Dc ground connection.
   O2-+ 6      23+-POT Y    15-22   D0-D7   Data Bus connections.
 R/_W-+ 7      22+-D7       23      POT Y   Input to a A/D converter used to
  _CS-+ 8      21+-D6                       detect the value of a variable
   A0-+ 9      20+-D5                       resistor. Commonly connected to
   A1-+10      19+-D4                       game paddles.
   A2-+11      18+-D3       24      POT X   Same as POT Y.
   A3-+12      17+-D2       25      VCC     5VDC.
   A4-+13      16+-D1       26      EXT IN  External audio input.
  GND-+14      15+-D0       27      A.OUT   Audio output. Should be AC coupled
      |          |                          to audio amp.
      +----------+          28      Vdd     12VDC.





















~
                               U7 - 906107-01
                            6510 MICROPROCESSOR

          PIN               1       O1      Phase 1 clock input. This clock
       ASSIGNMENT                           input is used to develop the
      +----------+                          internal overlapping phase 2
      |          |                          clock. 1MegHz or 2 MegHz
   O1-+ 1      40+-_RES                     speeds.
  RDY-+ 2      39+-O2       2       RDY     Single step operation input. A
 _IRQ-+ 3      38+-R/_W                     low applied will cause the
 _NMI-+ 4      37+-DB0                      processor to halt. The current
  AEC-+ 5      36+-DB1                      address line being fetched will
  VCC-+ 6      35+-DB2                      be on the address bus. Can also
   A0-+ 7      34+-DB3                      be used to interface slower
   A1-+ 8      33+-DB4                      devices to the microprocessor.
   A2-+ 9      32+-DB5      3       IRQ     Interrupt request input. When a
   A3-+10      31+-DB6                      low pulse is applied a jump to
   A4-+11      20+-DB7                      a location specified by the
   A5-+12      29+-P0                       contents of FFFE and FFFF will
   A6-+13      28+-P1                       occur to service the interrupt,
   A7-+14      27+-P2                       if the interrupt mask flag is
   A8-+15      26+-P3                       not set. This is a maskable
   A9-+16      25+-P4                       interrupt.
  A10-+17      24+-P5       4       NMI     Non-maskable interrupt input. A
  A11-+18      23+-A15                      low transition will cause a
  A12-+19      22+-A14                      jump to a location specified by
  A13-+20      21+-GND                      FFFA and FFFB to a subroutine
      |          |                          which will service the
      +----------+                          interrupt.
                            5       AEC     Address enable control input. A
                                            low applied to will cause the
                                            address bus to enter hi
                                            impedance state, so other
                                            devices can control the address
                                            bus.
                            6       VCC     5VDC input.
                            7-20    A0-A15  Address bus outputs.
                            22,23           Unidirectional bus used to
                                            address memory and I/O devices.
                                            The address bus can be disabled
                                            by controlling the AEC input.
                            21      GND     Dc ground connection.
                            24-29   P0-P5   I/O bidirectional port. This
                                            port can be controlled via
                                            memory locations 0000 and 0001.
                                            0001 = Output register
                                            0000 = Data direction register
~
                            30-37   DB0-DB7 Bidirectional data bus. This is
                                            the bus that passes the data
                                            to or from any I/O device or
                                            memory.
                            38      R/W     Read/Write output. The
                                            processor generates a low level
                                            when writing, and a high level
                                            when reading. This signal is
                                            usually decoded for read or
                                            write operations to memory or
                                            I/O.
                            39      O2      Phase 2 output. The processor
                                            generates this clock signal
                                            from the phase 1 clock applied.
                                            The two clock signals are 180
                                            degrees out of the phase. The
                                            phase 2 clock is used in
                                            decoding I/O and memory on the
                                            positive half cycle.
                            40      RES     Reset input interrupt. A low
                                            pulse causes a jump to a
                                            subroutine specified by FFFC
                                            and FFFD, which will initialize
                                            the all processor controlled
                                            devices. This occurs during a
                                            power up sequence.
            -----------------------------------------
          PIN
       ASSIGNMENT
      +----------+
      |          |
 PE+ -+ 1      28+-VCC            U17 - 906114-01
   I7-+ 2      27+-I8               PROGRAMMABLE
   I6-+ 3      26+-I9            LOGIC ARRAY (PLA)
   I5-+ 4      25+-I10
   I4-+ 5      24+-I11
   I3-+ 6      23+-I12
   I2-+ 7      22+-I13
   I1-+ 8      21+-I14
   I0-+ 9      20+-I15
   F7-+10      19+-CE
   F6-+11      18+-F0
   F5-+12      17+-F1
   F4-+13      16+-F2
  GND-+14      15+-F3
      |          |
      +----------+
~
                              U19 - 906109-01
                            6567 VIDEO INTERFACE
                              CHIP II (VIC II)

                                    PIN
                                 ASSIGNMENT
                                +----------+
                                |          |
                            DB6-+ 1      40+-VCC
                            DB5-+ 2      39+-DB7
                            DB4-+ 3      38+-DB8
                            DB3-+ 4      37+-DB9
                            DB2-+ 5      36+-DB10
                            DB1-+ 6      35+-DB11
                            DB0-+ 7      34+-A10
                           _IRQ-+ 8      33+-A9
                             LP-+ 9      32+-A8
                            _CS-+10      31+-A7
                           R/_W-+11      20+-A6 ("1")
                             BA-+12      29+-A5
                            VDD-+13      28+-A4
                          COLOR-+14      27+-A3
                       SYNC/LUM-+15      26+-A2
                            AEC-+16      25+-A1
                            PH0-+17      24+-A0
                           _RAS-+18      23+-A11
                           _CAS-+19      22+-PHIN
                            VSS-+20      21+-PHCL
                                |          |
                                +----------+
                                MULTIPLEXED
                          ADDRESSES IN PARENTHESES


    1-7/39  DB0-DB7 Processor data bus connections. Bidirectional data.
    8       IRQ     Interrupt output. Generates a interrupt signal to the
                    processor indicating service is needed. The light pen
                    input can be acknowledged thru use of this interrupt.
    10      CS      Chip select input. A low signal selects the VIC II.
    11      R/W     Processor read/write connection.
    12      BA      Bus available output. A low pulse output indicates the
                    VIC II chip wants control of the processor network to
                    process faster video operations that the system clock
                    can handle.
    13      VDD     12VDC input.
    14      COLOR   Output contains chrominance, color reference burst, and
                    color of display data.
~
    15      SYNC/   Output containing video, horizontal and vertical sync,
            LUM     and luminance information.
    16      AEC     Address enable output. This is usually connected to the
                    processor AEC input controlling the address bus.
                    AEC = 0 processor address bus disabled, refresh ram.
                    AEC = 1 processor address bus enabled. This allows
                            transparent system operations.
    17      PH0     Phase 0 output. Generated from the phase in signal.
    18      RAS     Row address strobe output. Selects proper row when
                    addressing dynamic ram for read/write operations or
                    refresh.
    19      CAS     Column address strobe output. Selects proper column
                    when addressing dynamic memory for read or write
                    operation.
    20      VSS     Ground connection.
    21      PHCL    Color clock, 14.31818 MHZ NTSC.
    22      PHIN    Clock input. Determines the dot transfer rate to the
                    display.
    23-24   A0-A13  Dual function address bus. During a microprocessor read
                    or write operation (AEC = 1), A0 thru A5 are inputs
                    used to address 47 internal registers. When AEC = 0 =
                    O2 is low, then A0 thru A13 are outputs used to refresh
                    dynamic memory.
    35-38   D8-D11  Data bus extension. Color display memory data.
            A8-A11  Address bus extension. Color display memory addressing.
    40      VCC     5VDC input.





















~
                              U9 -12, U21 - 24
                              64K DYNAMIC RAM
                                 901505-01

                                    PIN
                               CONFIGURATION
                                +----------+
                                |          |
                             NC-+ 1      16+-VSS
                            DIN-+ 2      15+-_CAS
                            _WE-+ 3      14+-DOUT
                           _RAS-+ 4      13+-A6
                             A0-+ 5      12+-A3
                             A2-+ 6      11+-A4
                             A1-+ 7      10+-A5
                            VCC-+ 8       9+-A7
                                |          |
                                +----------+


 +------------+------------+------------+--------+--------+--------+---------+
 |COMMODORE   |APPROVED    |VENDOR      |ACCESS  |        |    POWER         |
 |PART        |SOURCE      |PART        |TIME    |CYCLES  |ACTIVE  |STANDBY  |
 |NUMBER      |OF SUPPLY   |NUMBER      |(ns)    |(ns)    |(MW)    |(MAX)(MW)|
 +------------+------------+------------+--------+--------+--------+---------+
 |901505-01   |HITACHI     |HM4864-3    |200     |335     |330     |20       |
 |901505-01   |NEC         |uPD4164-2   |200     |375     |250     |28       |
 |901505-01   |MITSUBISHI  |M5K416NS-20 |200     |330     |275     |28       |
 |901505-01   |MOSTEK      |MK4564N-20  |200     |345     |300     |22       |
 |901505-01   |OKI         |MSM3764-20  |200     |330     |248     |23       |
 |901505-01   |HITACHI     |HM4864P-3   |200     |335     |330     |20       |
 |901505-01   |MATSUSHITA  |MN4164P-20  |200     |330     |275     |27.5     |
 |            |(PANASONIC) |            |        |        |        |         |
 |901505-01   |SIEMENS     |HYB4164-3   |200     |330     |150     |20       |
 |901505-01   |SHARP       |LH2164-Z1   |200     |330     |248     |28       |
 |901505-01   |HITACHI     |HM4864AP-3  |200     |330     |242     |20       |
 |901505-01   |TOSHIBA     |TMM4164AP-20|200     |330     |275     |22       |
 +------------+------------+------------+--------+--------+--------+---------+




[Figure: DRAM functional diagram]



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