SX 64 FDD board

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 NumberRemarks Memory Location/bit
UA1 TMM2016PRAM$0000-$07FF
UA3ROM$E000-$FFFF
UA4ROM$C000-$DFFF
UB274LS04
UBC36522VIA 1 (I/O)$1800-$180F
UBC46502ACPU
UC274LS00
UD274LS42
UD374LS86
UD4
UDC56522VIA 2 (Disk)$1C00-$1C0F
UE274LS14
UE37406
UF2M54532P
ULN2064
UF37404
UF5GATE ARRAY
UG47407
UG574LS193
UH1592Video AMP
UH49602One Shot
UH574LS197
UJ1592Video AMP
UJ474LS86
UK4LM311Comparator

Schematics

Commodore SX 64 Board 251110 Left

Commodore SX 64 Board 251110 Left

Commodore SX 64 Board 251110 Right

Commodore SX 64 Board 251110 Right


Board Image

251109 Rev 1

251109 Rev 1

251109 Rev A

251109 Rev A

251433B Rev A

251433B Rev A

 

Leave a Reply

Your email address will not be published. Required fields are marked *