Commodore SX 64 FDD Board
- three versions known (to me) 251109 Rev 1, 251109 Rev A and 251433B Rev A, the difference between the 251109 and 251433 seems to be IC UD4 that is missing in 251109, I couldn’t find any differences between 251109 Rev 1 and Rev A.
- is basically a 1541 Floppy disk drive controller.
Integrated Circuits
PCB Identifier | Chip Number | Remarks | Memory Location/bit |
---|---|---|---|
UA1 | TMM2016P | RAM | $0000-$07FF |
UA3 | ROM | $E000-$FFFF | |
UA4 | ROM | $C000-$DFFF | |
UB2 | 74LS04 | ||
UBC3 | 6522 | VIA 1 (I/O) | $1800-$180F |
UBC4 | 6502A | CPU | |
UC2 | 74LS00 | ||
UD2 | 74LS42 | ||
UD3 | 74LS86 | ||
UD4 | |||
UDC5 | 6522 | VIA 2 (Disk) | $1C00-$1C0F |
UE2 | 74LS14 | ||
UE3 | 7406 | ||
UF2 | M54532P ULN2064 | ||
UF3 | 7404 | ||
UF5 | GATE ARRAY | ||
UG4 | 7407 | ||
UG5 | 74LS193 | ||
UH1 | 592 | Video AMP | |
UH4 | 9602 | One Shot | |
UH5 | 74LS197 | ||
UJ1 | 592 | Video AMP | |
UJ4 | 74LS86 | ||
UK4 | LM311 | Comparator |
Schematics
Board Image