Ruben's Retro Corner
Commodore 128 (1985)

The 128 was Commodore's 8-bit swan song, released in 1985.

The Commodore 128 was three computers in one: a C128 with improved BASIC and 128 KiB of memory, a C64 mode that was almost entirely compatible, and a CP/M machine running on a Zilog Z80. It was designed by Bil Herd and his team, the same people behind the 264 line. A sleek new beige case with larger vents, a number pad, and a set of extra function keys for use in C128 mode were the biggest visual differences. This machine meant business, but also had that legendary C64 sprite and sound hardware.

I don't think it's a stretch to call it the most capable 8-bit machine of all time, as its exhaustive parts lists and complicated motherboard can attest! Sure, there have been machines with multiple CPUs, but consumer hardware on different instruction sets, on the same board!?

Josh Nunn of The Geekorium gave me his PAL Commodore 128 after hearing me wax lyrical about the machine on an episode of my silly podcast. Over time its 80-column circuitry and some of its higher memory banks have started having issues, which I've yet to fix. I couldn't find a replacement for the missing F7/F8 key, but I did find a little extra HELP.

Photos

Components

System

Component	Part	Year	State	Memo
Name	josh	-		The gracious person who gave it to me :)
Case	Stock	1985		Retrobrighted and fixed grounding strap
Dimensions		-	-
Keyboard	Stock (fixed)	1985		Repaired function keys, replaced F7/F8
Motherboard	Stock	1985		Mostly works, but not 80-column mode

ICs

Component	Part	Socket	Month	State	Memo
CIA 1	MOS 6526	U1	42, 85
CIA 2	MOS 6526	U4	42, 85		Has "S" printed on top
SID	MOS 6581 R3	U5	42, 85
CPU/MPU	MOS 8502 R0	U6	40, 85		Used in C128 and C64 modes
MMU	MOS 8722 R2	U7	43, 85		Memory management unit
CPU Z80	Zilog Z80 B	U10	35, 85		Z8400BPS
PLA	#TODO: Add here	U17
Character ROM	MOS 390059-01	U18	19, 85		"CBM M452995 8541H"
Colour SRAM	Hitachi HM6116P-4	U19	27, 85
VIC-II	MOS 8566	U21	41, 85		PAL version
VDC	MOS 8563 R2	U22	07, 86		Needs fixing. 64 K SaRuMan worked
Clock Gen.	MOS 8701	U28	41, 85		"F6 S" printed on top
KERNAL ROM	MOS 251913-01	U32	41, 85		With BASIC. "Taiwan 26011D-370"
BASIC LO ROM	MOS 318018-02	U33	41, 85		"Taiwan 26011D-290"
BASIC HI ROM	MOS 318019-02	U34	41, 85		"Taiwan 26011D-291"
128 KERNAL ROM	MOS 318020-03	U35	40, 85		"Taiwan 26011D-292"
User Socket	-	U36	-

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