Re: CST Thor 1 EPROM problem
Posted: Tue Mar 26, 2019 8:03 am
Hi Derek - thanks a lot for trying! Your experience and mine does suggest to me that perhaps there was not that much data on the Thor 1 serial number/watermark EPROM..... In terms of interfacing the Thor ROM board directly to a QL via the ROM connector, I’ll look at the Thor/QL schematics in the Thor technical manual...
And Dave - thanks to you for your helpful suggestions - I can’t send PMs as yet, but I’ve seen some of Urs König‘s QL videos on YouTube, and I think he has a website, so I can probably find a way of contacting him. In terms of the Thor 1 ROMs on Dilwyn’s site, these all appear to be various versions of the Thor 1 QDOS extensions, and I’ve not found anything there relating to the serial no/watermark EPROM. I’ve been scouring the Thor 1 technical manual that you linked to, and it certainly describes a process whereby the Thor OS reads the serial number/watermark, but there’s no real detail on the contents of the serial number/watermark EPROM, though the data format of the serial number is described.
So, I’m beginning to think that all the important Thor 1 specific OS extensions are in the Thor 4.xx EPROM, and that the second 8k EPROM is just a machine specific serial number container and doesn’t harbour much else. Without an example of a working Thor 1 serial number EPROM, I think it will be difficult to recreate such a thing, but I wonder about disassembling the Thor 4.00 EPROM code to see whether the code could be modified to bypass or spoof the serial number read/test ... ??? Alternatively, a dissassembly might allow a sufficient understanding of the serial EPROM that it could be recreated...
And Dave - thanks to you for your helpful suggestions - I can’t send PMs as yet, but I’ve seen some of Urs König‘s QL videos on YouTube, and I think he has a website, so I can probably find a way of contacting him. In terms of the Thor 1 ROMs on Dilwyn’s site, these all appear to be various versions of the Thor 1 QDOS extensions, and I’ve not found anything there relating to the serial no/watermark EPROM. I’ve been scouring the Thor 1 technical manual that you linked to, and it certainly describes a process whereby the Thor OS reads the serial number/watermark, but there’s no real detail on the contents of the serial number/watermark EPROM, though the data format of the serial number is described.
So, I’m beginning to think that all the important Thor 1 specific OS extensions are in the Thor 4.xx EPROM, and that the second 8k EPROM is just a machine specific serial number container and doesn’t harbour much else. Without an example of a working Thor 1 serial number EPROM, I think it will be difficult to recreate such a thing, but I wonder about disassembling the Thor 4.00 EPROM code to see whether the code could be modified to bypass or spoof the serial number read/test ... ??? Alternatively, a dissassembly might allow a sufficient understanding of the serial EPROM that it could be recreated...