250441

• Only mentioned in official CBM-documents, but no known PCB exists

• PCB ASSY NO. 250441

• Schematic Number #251469 (same as PCB ASSY NO. 250425)

• Released in 1985 (if ever)

• 8-pin board (CN5-Video port has 8 pins)

• reduced oscillator circuit with component changes

• All circuits remain the same as schematic #251469 except for a few component location changes

• Resistors 28, 29, 30, 36 and 48 were reduced to Resistor Pack RP5

• Diodes CR100-105 are no longer piggybacked: their locations are now CR9, CR12-16

Components’ placement

PCB identifier	IC number	IC type	Memory location/bit
U1	6526	CIA 1	$DC00-$DCFF
U2	6526	CIA 2	$DD00-$DDFF
U3	901226	BASIC ROM	$A000-$BFFF
U4	2364	KERNAL ROM	$E000-$FFFF
U5	2332	CHARACTER ROM	$D000-$DFFF
U6	2114L	SRAM 1K x 4	$D800-$DBFF
U7	6510	CPU	N/A
U8	7406	Logic NOT (Hex Inverter)	N/A
U9	4164	DRAM 64K x 1	D1
U10	4164	DRAM 64K x 1	D3
U11	4164	DRAM 64K x 1	D5
U12	4164	DRAM 64K x 1	D7
U13	74LS257	Multiplexor	N/A
U14	74LS258	Multiplexor	N/A
U15	74LS139	Demultiplexor	N/A
U16	4066	Quad Bilateral Switch	N/A
U17	82S100/906114-01	PLA	N/A
U18	6581	SID	$D400-$D7FF
U19	6567 (NTSC)/6569 (PAL)	VIC-II	$D000-$D3FF
U20	LM556	Dual Timer	N/A
U21	4164	DRAM 64K x 1	D0
U22	4164	DRAM 64K x 1	D2
U23	4164	DRAM 64K x 1	D4
U24	4164	DRAM 64K x 1	D6
U25	74LS257	Multiplexor	N/A
U26	74LS373	8 bit 3-state Latch	N/A
U27	74LS08	Logic AND	N/A
U28	4066	Quad Bilateral Switch	N/A
U31	7701/8701	Oscillator	N/A