Hi All,
As I previously mentioned in the post, http://www.cpcwiki.eu/forum/index.php?topic=2836.0 (http://www.cpcwiki.eu/forum/index.php?topic=2836.0)
I have 2 Australian delivered and Awa distributor coded 6128's with the main PCB revision of MC0020C.
As this PCB is not mentioned in the "Mainboard" pictures on the wiki I took a photo of one today while it was apart...
One thing to note with this PCB is that both IC's 107 (D8255AC-5) & 110 (SN74LS132N) are in a socket, my other MC0020C PCB these are directly soldered to the PCB.
The reason for pulling this apart today was that while I was testing this 6128, it did not appear to boot but instead just a scrolling screen.
This 6128 had this issue initially when I got it years ago. The issue is related to IC's 107 (D8255AC-5) and/or its socket. Once I press this back in, all is good (The PIO chip has a direct connection to the VSYNC on the CRT controller - IC 108.
Also, both these 6128's have close serial numbers and were old High School computers from a school in South Australia...I was initially thinking that the one with the sockets for IC's 107 & 110 had been repaired at some point (they did not have any owners after their time as school computers...but I'm sure they had a workout for a good few years).
Cheers,
Shane
Great!!! Thanks for the photos, will add them to the wiki page!