2001 Main Logic Assembly
The 8K Main Logic Assembly Parts Cross Reference is Commodore Business Machines' parts list for the Commodore PET 2001 system board: three letter-size sheets on the company's Santa Clara letterhead, 67 numbered lines giving reference designator, description, Commodore part number and dealer price. This copy is a colour scan at 400 dpi.[1]
The PDF is byte-identical to File:Commodore PET 2001 Main Logic Assembly Parts List.pdf, the copy cited from Commodore PET 2001 Service Documentation and Commodore PET 2001 Capacitor Replacement Guide.
An earlier issue of the same list, on Commodore's Palo Alto letterhead, is held as images at System Board Parts List (1 of 3), System Board Parts List (2 of 3) and System Board Parts List (3 of 3). It has no line numbers or dealer prices, gives UH1 as the 6540-011 (901439-01) or 2316B-01 (901447-01) with the 6540-019 and 2316B-09 typed in afterwards as revisions, numbers the sockets 904153, and has the two 901446 part numbers corrected by hand to 901447.[2]
Contents
[edit | edit source]Sheet 1 lists the capacitors, diodes, LED, headers, transistors and the first resistors (lines 1-22); sheet 2 the remaining resistors and the ICs from UA1 to UE6 (lines 23-45); sheet 3 the rest of the ICs, the ROMs and the IC sockets (lines 46-67).[1]
| Position | Part as printed | Commodore part no. |
|---|---|---|
| C1, C2, C14 | 0.01 µF 100 V ceramic | 900010-38 |
| C5, C11, C12, C13 | 1.0 µF 25 V tantalum | 900402-13 |
| C6 | 0.1 µF 50 V ceramic | 900010-20 |
| C7-C10 | 47 µF 16 V electrolytic | 900100-33 |
| C15-C49 | 0.1 µF 10 V ceramic | 900010-39 |
| CR1, CR2, CR3 | 1N5402 3 A 200 V | 900753-01 |
| Q1, Q4 | TIP29 | 902653-01 |
| Q2, Q5 | 2N4401 | 902652-01 |
| Q3, Q6 | 2N3904 | 902658-01 |
| UF3 | 6502 MPU | 901435-01 |
| UB8, UG8 | 6520 PIA | 901436-01 |
| UA5 | 6522 VIA | 901437-01 |
| UA7, UA8, UA9 | MC3446 interface bus | 901524-01 |
| UC3, UC4, UI1-UI8, UJ1-UJ8 | 6550 RAM, or 2114 RAM | 901438-01, or 901453-01 |
| UA2 | 6540-010 character generator, or 2316B-08 | 901439-08, or 901447-08 |
C7-C10 are the only aluminium electrolytics in the list. Q1 and Q4 are the cassette motor drivers on schematic sheet 1, switching the unregulated +9 V to the second and first cassette motors.[1][3]
Each ROM position has two lines, one for a 6540 ROM and one for a 2316B:
| Position | 6540 ROM | Part no. | 2316B ROM | Part no. |
|---|---|---|---|---|
| UH1 | 6540-019 | 901439-09 | 2316B-09 | 901447-09 |
| UH2 | 6540-013 | 901439-02 | 2316B-03 | 901447-03 |
| UH3 | 6540-015 | 901439-03 | 2316B-05 | 901447-05 |
| UH4 | 6540-016 | 901439-04 | 2316B-06 | 901447-06 |
| UH5 | 6540-012 | 901439-05 | 2316B-02 | 901447-02 |
| UH6 | 6540-014 | 901439-06 | 2316B-04 | 901446-04 |
| UH7 | 6540-018 | 901439-07 | 2316B-07 | 901446-07 |
The UH6 and UH7 2316B part numbers are printed with the prefix 901446 where every other 2316B line has 901447. The sheet lists both a 28-pin socket (904150-05) and a 24-pin socket (904150-04) against UA2 and UH1-UH7, a 40-pin socket for UA5, UB8, UF3 and UG8, and a 22-pin socket for the eighteen RAM positions.[1]
What it does not contain
[edit | edit source]The list stops at C49 and has no VR entries. Sheet 2 of the main logic schematic shows the board's power section, which the list omits: capacitors C50 and C51 (0.02 µF 500 V) across the rectifiers at connector J8, and four regulators VR3-VR6 with test points TP1-1 to TP1-4, each with one of C7-C10 beside it. Sheet 1 also shows two 7.2 V zener diodes, VR1 and VR2, in the cassette motor circuit, which are not listed either.[3] The mains transformer and the logic supply's reservoir capacitor are not on this board; see Commodore PET 2001 Service Documentation.
There is no placement drawing for the main logic board in this document. The display assembly has one, at Video Board Parts Layout.
The LM555 timer is listed against the designation "UDE9", which is how the schematic labels it too.[1][3]
Pages that cite this document
[edit | edit source]- Commodore PET 2001 Service Documentation: the index to the PET 2001 documents held here
- System Board Parts List (1 of 3), System Board Parts List (2 of 3) and System Board Parts List (3 of 3): the earlier Palo Alto issue of the list, as images
- Schematic 320130 (Sheet 1 of 3, Static PET)
Download: 2001_main_logic_assembly.pdf
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Commodore Business Machines, Inc., 8K Main Logic Assembly Parts Cross Reference, 3 sheets. Hosted as File:2001_main_logic_assembly.pdf.
- ↑ Commodore Business Machines, Inc., 901 California Avenue, Palo Alto, Main Logic Assembly Parts Cross Reference, sheets 2 and 3. Hosted as File:parts-2.gif and File:parts-3.gif.
- ↑ 3.0 3.1 3.2 Commodore Business Machines, PET Computer Main Logic, drawing 320130 (sheet 1, "Circuitry common to all PET computers") and drawing 320026 (sheet 2, Memory Section, board assembly 320008). Hosted as File:Commodore PET 2001 Main Logic Schematic (320008).pdf.
