Zimmers.NET Files (formerly ftp.funet.fi)


The Commodore Model B service manual and schematic diagrams


Disk drives
System firmware


314010-06-i.gif 1998-03-29 29724
Service manual, B model computer: (Jan. 1985, PN-314010-06), title page
314010-06-ii.gif 1998-03-29 27628
Service manual, B model computer: table of contents
314010-06-p1.gif 1998-03-29 58149
Service manual, B model computer: Page 1: block diagram
314010-06-p2.gif 1998-03-29 46741
Service manual, B model computer: Page 2: B model parts list
314010-06-p3-left.gif 1998-03-29 60694
Service manual, B model computer: Page3: 8256048 board left side
314010-06-p3-right.gif 1998-03-29 79404
Service manual, B model computer: Page 3: 8256048 board right side
314010-06-p4.gif 1998-03-29 74105
Service manual, B model computer: Page 4: 8256048 PCB parts
314010-06-p5.gif 1998-03-29 66252
Service manual, B model computer: Page 5: 8256048 PCB parts, continued
314010-06-p6-left.gif 1998-03-29 40857
Service manual, B model computer: Page 6: keyboard matrix left side
314010-06-p6-right.gif 1998-03-29 42640
Service manual, B model computer: Page 6: keyboard matrix right side

4256004-01-left.gif 1998-03-29 35712
Commodore CBM-II B model Switching power supply, left side
4256004-01-parts.gif 1998-03-29 58167
Commodore CBM-II B model Switching power supply, Parts list
4256004-01-right.gif 1998-03-29 44598
Commodore CBM-II B model Switching power supply, right side

4256041-01of15.gif 1998-09-28 346636
Commodore P500 Color Computer: address & data buffers, arbitration logic
4256041-02of15.gif 1998-09-27 264513
Commodore P500 Color Computer: system decode & buffer control
4256041-03of15.gif 1998-09-28 292293
Commodore P500 Color Computer: VIC; video memory; video bus buffers
4256041-04of15.gif 1998-09-27 192900
Commodore P500 Color Computer: SID; 192k DRAM array refresh logic
4256041-05of15.gif 1998-09-28 279736
Commodore P500 Color Computer: 192k DRAM address mux & control
4256041-06of15.gif 1998-09-27 238991
Commodore P500 Color Computer: 192k*8 DRAM array [64k standard, 128k optional]
4256041-07of15.gif 1998-09-28 223503
Commodore P500 Color Computer: 64k DRAM array and address mux
4256041-08of15.gif 1998-09-28 194905
Commodore P500 Color Computer: system ROM/RAM array
4256041-09of15.gif 1998-09-28 273583
Commodore P500 Color Computer: gameport interface; keyboard interface; RS232C interface
4256041-10of15.gif 1998-09-27 295118
Commodore P500 Color Computer: interrupt prioritization; IEEE488 interface; user/game port interface
4256041-11of15.gif 1998-09-28 258517
Commodore P500 Color Computer: cassette i/f port
4256041-12of15.gif 1998-09-27 193891
Commodore P500 Color Computer: main oscillators & PLL
4256041-13of15.gif 1998-09-28 150690
Commodore P500 Color Computer: video output circuit
4256041-14of15.gif 1998-09-27 289443
Commodore P500 Color Computer: [List of power filter capacitors for each IC]
4256041-15of15.gif 1998-09-28 211721
Commodore P500 Color Computer: [FPLA logic equations]

4256047-01.jpg 2018-06-22 3210191
4256047-02.jpg 2018-06-22 2793038
4256047-03.jpg 2018-06-22 2792216
CBM-II z80 board schematic.

8088.gif 2002-03-05 155989
8088.txt 2002-04-19 10991
The 8088 co-processor board for B-series machines. Reverse engineered
by Ruud Baltissen http://ruud.c64.org.

8256043-01of14-left.gif 1998-03-29 61535
CBM-II LP: schematic P1, left side: address & data buffers, bus arbitration
8256043-01of14-right.gif 1998-03-29 56042
CBM-II LP: schematic P1, right side: address & data buffers, bus arbitration
8256043-02of14-left.gif 1998-03-29 27636
CBM-II LP: schematic P2, left side: master timing
8256043-02of14-right.gif 1998-03-29 47170
CBM-II LP: schematic P2, right side: master timing
8256043-03of14-left.gif 1998-03-29 40539
CBM-II LP: schematic P3, left side: DRAM address & refresh
8256043-03of14-right.gif 1998-03-29 28812
CBM-II LP: schematic P3, right side: DRAM address & refresh
8256043-04of14-left.gif 1998-03-29 31695
CBM-II LP: schematic P4, left side: DRAMs, segments 1-2
8256043-04of14-right.gif 1998-03-29 29054
CBM-II LP: schematic P4, right side: DRAMs, segments 1-2
8256043-05of14-left.gif 1998-03-29 31825
CBM-II LP: schematic P5, left side: DRAMs, segments 3-4
8256043-05of14-right.gif 1998-03-29 29841
CBM-II LP: schematic P5, right side: DRAMs, segments 3-4
8256043-06of14-left.gif 1998-03-29 27122
CBM-II LP: schematic P6, left side: ROM array, 1k×8 static RAM
8256043-06of14-right.gif 1998-03-29 32195
CBM-II LP: schematic P6, right side: ROM array, 1k×8 static RAM
8256043-07of14-left.gif 1998-03-29 28442
CBM-II LP: schematic P7, left side: system decode
8256043-07of14-right.gif 1998-03-29 43144
CBM-II LP: schematic P7, right side: system decode
8256043-08of14-left.gif 1998-03-29 26866
CBM-II LP: schematic P8, left side: CRTC, video shift register
8256043-08of14-right.gif 1998-03-29 32189
CBM-II LP: schematic P8, right side: CRTC, video shift register
8256043-09of14-left.gif 1998-03-29 22887
CBM-II LP: schematic P9, left side: video RAM, address mux, latch
8256043-09of14-right.gif 1998-03-29 26607
CBM-II LP: schematic P9, right side: video RAM, address mux, latch
8256043-10of14-left.gif 1998-03-29 45846
CBM-II LP: schematic P10, left side: keyboard port, RS232C
8256043-10of14-right.gif 1998-03-29 42104
CBM-II LP: schematic P10, right side: keyboard port, RS232C
8256043-11of14-left.gif 1998-03-29 62363
CBM-II LP: schematic P11, left side: user I/O ports, IEEE
8256043-11of14-right.gif 1998-03-29 50878
CBM-II LP: schematic P11, right side: user I/O ports, IEEE
8256043-12of14-left.gif 1998-03-29 53904
CBM-II LP: schematic P12, left side: SID, dot clock oscillator, expansion connector
8256043-12of14-right.gif 1998-03-29 50410
CBM-II LP: schematic P12, right side: SID, dot clock oscillator, expansion connector
8256043-13of14.gif 1998-03-29 27850
CBM-II LP: schematic P13: video output, power indicator
8256043-14of14.gif 1998-04-17 81574
CBM-II LP: schematic P14: I.C. count, power consumption

8256059-01.gif 1998-05-28 159301
CBM-II HP: schematic P1: address and data bus arbitration
8256059-02.gif 1998-06-02 104788
CBM-II HP: schematic P2: master timing
8256059-03.gif 1998-06-02 104071
CBM-II HP: schematic P3: dram address and refresh
8256059-04.gif 1998-06-02 91274
CBM-II HP: schematic P4: dram segment 1 and 2
8256059-05.gif 1998-05-29 92943
CBM-II HP: schematic P5: dram segment 3 and 4
8256059-06.gif 1998-05-29 81230
CBM-II HP: schematic P6: rom array, 1kx8 static rom
8256059-07.gif 1998-05-29 97112
CBM-II HP: schematic P7: system decode
8256059-08.gif 1998-05-29 102877
CBM-II HP: schematic P8: crtc, video shift reg outputs
8256059-09.gif 1998-06-01 76584
CBM-II HP: schematic P9: video ram, address mux, latch
8256059-10.gif 1998-06-02 116642
CBM-II HP: schematic P10: keyport port1 rs232c
8256059-11.gif 1998-06-02 150061
CBM-II HP: schematic P11: user i/o ports, ieee-488
8256059-12.gif 1998-06-02 136422
CBM-II HP: schematic P12: sid, casette, dotclk osc, expanse

cbm-610-psu-german.jpg 2020-10-19 692236
CBM 610 Power Supply schematic, uploaded by Christian Forstreuter

CBM-II-partial700Schematic.zip 2018-05-17 417579
Contains partial schematic of CBM 7xx series, drawn by Ruud Baltissen

cbm2-schematics-4256004-01-lp-ps.pdf 2020-07-27 89502
Commodore CBM-II B model Switching power supply, full schematic

cbm2-schematics-8256043-bl.pdf 2020-07-27 8375143
CBM-II LP Full Schematic doc

cbm2_hires_color_graphic_1_of_4.png 2018-06-23 1256894
cbm2_hires_color_graphic_2_of_4.png 2018-06-23 913450
cbm2_hires_color_graphic_3_of_4.png 2018-06-23 477415
cbm2_hires_color_graphic_4_of_4.png 2018-06-23 350418
Schematic of unknown CBM-II Hi-Res Graphic something

cbm500-700keyboardAdapter.jpg 2017-09-14 571729
Pinout useful to adapting a B500 keyboard for the B700 series. From Alessandro

cbm700_CEAG_Supply_C.pdf 2023-08-26 6363174
cbm700_CEAG_Supply_D-F.pdf 2023-08-26 6234949
cbm700_CEAG_Supply_US-B.pdf 2023-08-26 6318251
Schematic of B7x0 power supplies, drawn by Christian Forstreuter
** Note: The TDA 1060 pin 13 (over-voltage prot input) is
floating on many of these supplies, which can lead to failure. The
recommendation is to ground it to pin 12 if that is the case.

CBM700_CRT_Schematics.pdf 2021-09-14 1212990
Schematics for CRT board used in CBM 700 series, as well as the CBM 128-80 and

cbm700keyboardPinout.gif 2017-07-19 143540
cbm 700 (HP) keyboard pinout (by Liberalato Alessandro)

CBM_8088_CPU_co-processor_schematic.pdf 2017-10-20 6290321
Schematic to 8088 option card for CBM-II machines.

p500-keyboard.txt 1999-07-30 3512
Commodore P500 Keyboard Schematic. Composed by Tony Duell

parts.txt 2015-07-08 1779
Parts list for CBM-II series computers, from William Levak

README 1998-10-20 1169
General information about the Commodore Model II computers.
README500 1998-10-20 920
Information about the Commodore 500 a.k.a. PET II.

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