The Sinclair QL Forum

The ZX8301 is the 'Master Chip' of the Sinclair QL Professional Computer. Its purpose is documented in the Sinclair QL Service Manual. See:
http://www.sinclairql.net/srv/qlsm1.html#s1-p6

The chip designed by David Karlin and manufactured by Plessey. See:
http://www.sinclairql.net/story/The_lon ... Karlin.htm

There are two known editions of the chip, the CLA2310 and the later CLA2345. Their mask differs.

Way back in May 2014 I explored the die of a Sinclair ZX8301 CLA2345 chip with my newly acquired BRESSER MicroSet microscope. Another QLer is currently exploring a CLA2310. This motivated me to review my work and publish the material (both video and stills) I've shot using the microscope.

Videos:
https://www.youtube.com/watch?v=jx52phYHc9E
https://www.youtube.com/watch?v=bzN9zgPXcmo
https://www.youtube.com/watch?v=o79SPPTkVMg

Stills:
https://onedrive.live.com/?id=c250d8748 ... 748980CE5A

More to come from either me or other QLers.

QL forever!
Urs

This is why we need a Sinclair QL Hardware Resource page with all of these and the die pictures etc....

This is great! Do you think the pictures will allow to infer the schematics?

M68008 wrote:This is great! Do you think the pictures will allow to infer the schematics?

Thanks!

Intention is to 1) visualise the die surface in high resolution, 2) analyse and compare the two mask revisions, 3) reverse engineer the chip.

Yesterday I restarted the 2014 initiated microscope job. I’ve added a photo of my current setup to above mentioned OneDrive stills link.

Today was a good day! I had my dose of an hour quality QL time and even made a video. Two of my favourite hobbies combined.

ZX8301 CLA2345 die ultrasonic clean-up job
https://www.youtube.com/watch?v=na2v5dGrAlU

Result: Die of the CLA2345 cleaned using a ultrasonic cleaner. Ready for another try with the microscope.

Is there anything we can contribute that might advance this effort?

Keith Murphy also is also working on this - he has an 8301, a couple of 8302s and the HAL chip which he is investigating...

Dave wrote:Is there anything we can contribute that might advance this effort?

All good at the moment, thanks.

RWAP wrote:Keith Murphy also is also working on this - he has an 8301, a couple of 8302s and the HAL chip which he is investigating...

Yes, I know. Keith and I teamwork together since a few weeks. Keith has a CLA2310 and a ZX8302 die to take high-res pictures, I have a CLA2345 die to take high-res images from.

Nasta probably knows in detail the operation of these devices. I'm sure he has the skill, but not the time, to work out higher spec replacements.

He's probably staying quiet because time is such a premium.