250469

  • PCB ASSY NO. 250469

  • Schematic Number #252312

  • Released in 1987

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

  • KERNAL & BASIC ROMS combined into U4

  • New IC memory controller U8

  • This highly redesigned motherboard is commonly known as a “short board”

  • The “short board” used the new HMOS-chipset, featuring a new 64-pin PLA chip. The new “SuperPLA”, as it was dubbed, integrated many discrete components and Transistor–Transistor Logic (TTL) chips.

  • In the last revision of the C64C motherboard, the 2114 color RAM was integrated into the SuperPLA.

Components’ placement

PCB Identifier

IC number

IC type

Memory location/bit

U1

6526

CIA 1

$DC00-$DCFF

U2

6526

CIA 2

$DD00-$DDFF

U3

74LS08

N/A

U4

23128

BASIC and KERNAL ROM
$A000-$BFFF
$E000-$FFFF

U5

2332

CHARACTER ROM

$D000-$DFFF

U6

8500

CPU

N/A

U7

8562 (NTSC)/8565 (PAL)

VIC-II

$D000-$D3FF

U8
251715 (Rev.A, Rev.3, Rev.4)
252535 (Rev.B)

PLA

N/A

U9

8580

SID

$D400-$D7FF

U10

41464

DRAM 64K x 4

D0-D3

U11

41464

DRAM 64K x 4

D4-D7

U18

4066

Quad Bilateral Switch

N/A

U19

2114 (not on Rev.B)

SRAM 1K x 4

$D800-$DBFF

U20

8701

Oscillator

N/A

U21

4066

Quad Bilateral Switch

N/A

U22

7404

inverter

N/A

U23

7404

inverter

N/A