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Schematic 320135 (Complete, Board 320137): Difference between revisions

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Auto-created Commodore PET 2001 schematic page
 
P4 verification: real documentation page — identifies the sheet from its own title block, records that sheet 1 of every set is drawing 320130, and links the parts lists and display-assembly documents
 
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'''Commodore drawing #320135''', the complete three-sheet main logic schematic for '''PET 2001 board assembly #320137''', Commodore Business Machines, Inc., Palo Alto, California. Three A-size sheets, scanned at 400 dpi.
Assembly 320137 is the static PET 2001 board fitted with '''2316B ROMs and 2114 RAM'''.
== The three sheets ==
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table"
|-
! Sheet !! Drawing number in the title block !! Title !! Also on this wiki as
|-
| 1 of 3 || '''#320130''' — not #320135 || ''PET Computer Main Logic'' — "Circuitry common to all PET computers" || [[Schematic 320130 (Sheet 1 of 3, Static PET)]]
|-
| 2 of 3 || #320135 || ''PET Computer Main Logic — Memory Section'', pertaining to board assembly #320137 || [[Schematic 320135 (Sheet 2 of 3, Board 320137)]]
|-
| 3 of 3 || #320135 || ''PET Computer Main Logic — Video Logic'', pertaining to board assembly #320137 || [[Schematic 320135 (Sheet 3 of 3, Board 320137)]]
|}
'''Sheet 1 is the same drawing in all four sets.''' Its title block reads #320130 whichever board's PDF you open, which is why this wiki holds only one copy of it. Sheets 2 and 3 are the board-specific drawings and carry #320135.
== The four static board assemblies ==
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table"
|-
! Board assembly !! ROMs !! RAM !! Drawing number for sheets 2–3
|-
| 320008 || 6540 || 6550 || 320026
|-
| 320081 || 2316B || 6550 || 320082
|-
| 320132 || 6540 || 2114 || 320130
|-
| 320137 || 2316B || 2114 || 320135
|}
Commodore's note is printed on sheets 2 and 3 of every set: '''"All locations are same on all boards; only the specific components will differ on boards numbered 320132, 320081, 320137, 320008. The identifying board number is in upper left corner."''' So a component location read off one of these drawings is valid for any static PET 2001 board; only the fitted part changes.
== What these sheets contain ==
* '''Sheet 1''' — the 6502 at UF3, both 6520 PIAs (UB8, UG8), the 6522 VIA (UA5), the three MC3446 IEEE-488 transceivers at UA7–UA9, the LM555 retrace timer, the cassette interface with its TIP29 motor drivers and 7.2 V zeners, and the keyboard matrix pull-ups. '''No regulator''' — the board takes +5 V and +9 V unregulated from elsewhere in the machine.
* '''Sheet 2, Memory Section''' — the ROM and RAM array for this assembly specifically, which is what distinguishes the four boards.
* '''Sheet 3, Video Logic''' — character generator, video timing and the display output.
Some circuits on sheets 2 and 3 are marked with an asterisk and annotated '''"all ckts marked * are for BC machine only"''' — the business-keyboard variant.
== What these sheets do not contain ==
* '''No parts list.''' Values appear on the drawing where the drawing carries them. For the full component list with Commodore part numbers see [[System Board Parts List (1 of 3)]] and [[Commodore PET 2001 Service Documentation]].
* '''No power supply and no display circuitry.''' The mains transformer, the rectifiers, the 4700 µF reservoir and the flyback are all on the '''display assembly''' — see [[Video Board Schematic]] and [[Video Board Parts List (1 of 3)]].
Each sheet carries Commodore's 1970s trade-secret notice down the left edge. It is of historical interest only.
== Related pages ==
* [[Commodore PET 2001]] · [[Commodore PET 2001 Service Documentation]] · [[Commodore PET 2001 Capacitor Replacement Guide]] · [[Commodore PET 2001 General Maintenance]] · [[Commodore PET 2001 Troubleshooting]]
* The other three board sets: [[Schematic 320026 (Complete, Board 320008)]] · [[Schematic 320082 (Complete, Board 320081)]] · [[Schematic 320130 (Complete, Board 320132)]]
<pdf> File:320137.pdf </pdf>
<pdf> File:320137.pdf </pdf>


Download the file here: [[:File:320137.pdf|320137.pdf]]
Download: [[:File:320137.pdf|320137.pdf]]


[[Category:Commodore PET 2001 Schematics]]
[[Category:Commodore PET 2001 Schematics]]
[[Category:Commodore Documentation]]

Latest revision as of 02:05, 25 September 2026

Commodore drawing #320135, the complete three-sheet main logic schematic for PET 2001 board assembly #320137, Commodore Business Machines, Inc., Palo Alto, California. Three A-size sheets, scanned at 400 dpi.

Assembly 320137 is the static PET 2001 board fitted with 2316B ROMs and 2114 RAM.

The three sheets

[edit | edit source]
Sheet Drawing number in the title block Title Also on this wiki as
1 of 3 #320130 — not #320135 PET Computer Main Logic — "Circuitry common to all PET computers" Schematic 320130 (Sheet 1 of 3, Static PET)
2 of 3 #320135 PET Computer Main Logic — Memory Section, pertaining to board assembly #320137 Schematic 320135 (Sheet 2 of 3, Board 320137)
3 of 3 #320135 PET Computer Main Logic — Video Logic, pertaining to board assembly #320137 Schematic 320135 (Sheet 3 of 3, Board 320137)

Sheet 1 is the same drawing in all four sets. Its title block reads #320130 whichever board's PDF you open, which is why this wiki holds only one copy of it. Sheets 2 and 3 are the board-specific drawings and carry #320135.

The four static board assemblies

[edit | edit source]
Board assembly ROMs RAM Drawing number for sheets 2–3
320008 6540 6550 320026
320081 2316B 6550 320082
320132 6540 2114 320130
320137 2316B 2114 320135

Commodore's note is printed on sheets 2 and 3 of every set: "All locations are same on all boards; only the specific components will differ on boards numbered 320132, 320081, 320137, 320008. The identifying board number is in upper left corner." So a component location read off one of these drawings is valid for any static PET 2001 board; only the fitted part changes.

What these sheets contain

[edit | edit source]
  • Sheet 1 — the 6502 at UF3, both 6520 PIAs (UB8, UG8), the 6522 VIA (UA5), the three MC3446 IEEE-488 transceivers at UA7–UA9, the LM555 retrace timer, the cassette interface with its TIP29 motor drivers and 7.2 V zeners, and the keyboard matrix pull-ups. No regulator — the board takes +5 V and +9 V unregulated from elsewhere in the machine.
  • Sheet 2, Memory Section — the ROM and RAM array for this assembly specifically, which is what distinguishes the four boards.
  • Sheet 3, Video Logic — character generator, video timing and the display output.

Some circuits on sheets 2 and 3 are marked with an asterisk and annotated "all ckts marked * are for BC machine only" — the business-keyboard variant.

What these sheets do not contain

[edit | edit source]

Each sheet carries Commodore's 1970s trade-secret notice down the left edge. It is of historical interest only.

[edit | edit source]

Download: 320137.pdf