Board 250441-01 B2

250441-01 (B2)

    • 8-pin board (reduced oscillator with component changes).
    • PCB Assembly Number 240441-01.
    • Schematic Number 251469.
    • All circuits remain the same as the C64B (Schematic 251469) with a few component location changes.
      • Resistors 28, 29, 30, 36 and 48 were reduced to Resistor Pack RP5.
      • Diodes CR100-15 are no longer piggy-backed. Their locations are CR9, CR12-16.

Integrated Circuits

PCB Identifier Chip NumberRemarks Memory Location/bit
U1 6526
CIA 1$DC00-$DCFF
U26526
CIA 2$DD00-$DDFF
U32364Basic ROM$A000-$BFFF
U42364Kernal ROM$E000-$FFFF
U52332Character ROM$D000-$DFFF
U62114L-30 SRAM 1Kx4$D800-$DBFF
U76510CPU
U87406/7416Logic NOT (Hex Inverter)
U94164DRAM 64Kx1D1
U104164DRAM 64Kx1D3
U114164DRAM 64Kx1D5
U124164DRAM 64Kx1D7
U1374LS257Multiplexor
U1474LS258 Multiplexor
U1574LS139 Demultiplexor
U164066Quad Bilateral Switch
U1782S100 / 906114-01
PLA
U186581
SID$D400-$D7FF
U196567 (NTSC)/6569 (PAL)VIC-II $D000-$D3FF
U20LM556 Dual Timer
U214164DRAM 64Kx1D0
U224164DRAM 64Kx1D2
U234164DRAM 64Kx1D4
U244164DRAM 64Kx1D6
U2574LS257Multiplexor
U2674LS3738 bit 3-state Latch
U2774LS08Logic AND
U284066Quad Bilateral Switch
U317701/8701Oscillator

Schematics
No schematics…
Board Image
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