Commodore PC 10-II

Resources

Wiki
Service Manual
oldcomputer.info
zimmers.net (many files to download)

Internals

Motherboard

Jumper settings on the “Commodore PC Combined Motherboard”. If you wonder why this motherboard is called “combined”, please take a look at what Commodore PC 10 motherboard looks like.

RAM Extension Module

Power Supply

If voltages provided by the power supply are low and the “power ready” output is not active, please check the potentiometer located on the small vertical board first. It is prone to getting dirty inside and stops conducting. It may be enough to turn in back and forth to clean it up and it may start working again. Calibrate the 5V output with a multimeter after that. Recapping is also a very good idea.

The power connector has the following pinouts:

1   - Brown:  Power Good (+5V when power is ready)
2   - Red:    -12V
3   - Orange: +12V
4,5 - Blue:   Ground
6   - Yellow: +5V

Graphics Card

ATI Graphics Solution Rev.3 part number 168228. The configuration using on-board switches is on one of the pictures.

 

Floppy Disk Drives

360KB ALPS DFC222A05A

Both drives share the same cable without a “twist”, booting drive is set as DS0 and secondary drive as DS1. Other jumper configuration is on the pictures below.

Hard Disk Drive

My PC10-II did not come with a HDD, but I successfully connected Western Digital WX3 Winchester Controller and ST-251-1 MFM drive. Prior to being recognized by the PC10-II, the drive needs low level formatting – all instructions are in the controller user manual: Western_Digital_WX3-WX3R. I did not manage to get more than 20MB from this 40MB drive, but I don’t know if it is a matter of low level format parameters or PC configuration.

Reassembly

Some Dirt

DSC_0091

Advertisements

One thought on “Commodore PC 10-II

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s