Urs König writes:
“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_long_lost_interview_with_David_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=c250d8748980ce5a%2134212
https://onedrive.live.com/?id=c250d8748980ce5a%2134212&cid=C250D8748980CE5A&cid=C250D8748980CE5A
More to come from either me or other QLers.”