Hardware pinouts information and cables schemes

C128 Expansion Bus pinout

motherboard connector

bookmark this page

Available at the Commodore 128



Pin Name Description
1GNDSystem Ground
2+5VSystem Vcc
3+5VSystem Vcc
4/IRQInterrupt request
5R/WSystem Read/Write Signal
6DClock8.18MHz Video Dot Clock
7I/O1I/O Chip select $de00-deff
8/GAMESensed for memory map configuration
9/EXROMSensed for memory map configuration
10I/O2I/O Chip select $df00-dfff
11/ROMLExternal ROM select $8000-Bfff
12BABus available output
13/DMADirect memory access input
14D7Data bit 7
15D6Data bit 6
16D5Data bit 5
17D4Data bit 4
18D3Data bit 3
19D2Data bit 2
20D1Data bit 1
21D0Data bit 0
22GNDSystem Ground
AGNDSystem Ground
B/ROMHExternal ROM Select $c000-ffff
C/RESETSystem Reset Signal
D/NMINon-Maskable Interrupt
E1MHzSystem 1MHz clock
FTA15Translated address bit 15
HTA14Translated address bit 14
JTA13Translated address bit 13
KTA12Translated address bit 12
LTA11Translated address bit 11
MTA10Translated address bit 10
NTA9Translated address bit 9
PTA8Translated address bit 8
RSA7Shared address bit 7
SSA6Shared address bit 6
TSA5Shared address bit 5
USA4Shared address bit 4
VSA3Shared address bit 3
WSA2Shared address bit 2
XSA1Shared address bit 1
YSA0Shared address bit 0
ZGNDSystem Ground


This information should be correct, but may be not. Please, help us to improve this document!
Is this document CORRECT or INCORRECT? Your opinion will be used to establish document status (showed at the bottom).
Pinouts.ru > Motherboard connectors pinouts >  Pinout of C128 Expansion Bus and layout of connector
Document status: unknown
Source(s) of this and additional information: Commodore 128 Programmers reference guide. 0 reports
Last updated at Sat Jun 25 2005. Submit additions or corrections for this document. Is this document correct or incorrect? What is your opinion?
[Discuss at the forum] [Back to index] [SUBMIT new pinout]
This page contain parts under Copyright © 2000-2007 by pinouts.ru team.
No any portion of this webpage may be reproduced in any form without visible direct link to this page provided. Webmaster permission required in any other cases.
Efforts have been made to ensure this page is correct, but it is the responsibility of the user to verify the data is correct for their application.
7124 hits since March 4, 2005