Just when I'd convinced myself that I don't need more old computers, you have to go and get me all interested in the T600! ;-)
I was sort of interested anyway, because it's the only 8088 box I've ever heard of that runs neither MSDOS or CP/M-86. OTOH it was such a failure! I don't actually have anything useful to say, besides "good luck". Now I'm going to go *stay off ebay*. :-) Willard Sent from Samsung tablet -------- Original message -------- From Brian White <[email protected]> Date: 02/05/2017 12:42 PM (GMT-07:00) To Model 100 Discussion <[email protected]> Subject [M100] Model 600 basic rom I started to try to tease apart whether the basic.!55 file is maybe a copy of the option rom, even though it's too large to fit on a chip. I was thinking, maybe someone copied the option rom to disk via the system manager, and the disk/ram copy just gets some kind of headers or tails added to it which could be stripped off to get a rom image. To find out, I looked at the multiplan rom. I took a direct dump of the multiplan rom in an eprom programmer, which makes a guaranteed exact and working copy, because I then flashed that image back to a new eprom on a molex carrier and it worked. Then used the system manager to copy plan.!50 from rom to disk. Then removed the rom. Then copied from disk to ram. Then used xmodem to copy to a modern machine. Then compared those two images. Also armed with a tiny bit of info about rom structure from one of the developer manuals scanned in archive.org I seem to have found the opposite of what I was hoping. The the rom dump of multiplan is larger than the ram copy of the very same physical rom chip. The bulk of the two images are identical in the middle, but the rom image has 64 bytes of header prepended and 64 bytes of tail appended. And both versions have some dead space at the end, though the ram copy fills it with spaces and the rom image fills it with nulls. So basic.!55 remains a mystery. It's a ram/disk executable, which is larger than a rom image is possible to get. https://drive.google.com/folderview?id=0Bys6eLbSbYyhNHBIdk1rSlZORlk https://drive.google.com/folderview?id=0Bys6eLbSbYyhSFhFZ29TSEZkTUk
