Hi, I have an unusal east german PC, an A7150 aka CM1910. This Computer isn't build out of a motherboard and Slot Cards, it hast Modules and a passive Backplane with something like a Multibus-1 Bus using DIN41462 connectors, one for the System Bus (MMS16) the other for a Localbus. The Computer contains a CPU with 8086/87 and two SZ80-A based Subsystems for Graphics (using a NEC 7220) and Disk IO (2 Floppies and at ST506 Interface). The Computer is running DOS3.3, CP/M86 and a Unix called MUTOS, an realtime System called BOS1810 is also available, but I don't know an western equivalent for it. The 1810 ic comming from the soviet name of the 8086 Chips, they are named K1810xx. Here at robotrontechnik.de is a page about this Computer http://www.robotrontechnik.de/index.htm?/html/computer/a7150.htm buit it is in german. Here are some pictures of cards from this machine: http://www.robotrontechnik.de/index.htm?/html/computer/a7150.htm Ok, so far so good. This Machine is running DOS, but it isn't that much XT Compatible. The Graphics are emulating CGA (doublescan) for this mode but are capable to do 640x480 in 256 Colors. The Processor is clocked with 4,9 Mhz, which schould be a little faster than a average XT but the Bus arbitation brings in some more delay. The BUS is capable of multimastering which isn't used in this machine but takes time.. I have at least 3 of this machines, they aren't that rare in the former GDR and the Eastern Block. I've tried to put in a NEC V30 CPU which is working principially, but the BIOS in the Machine rejects it later. The Machine Checks are simple to precise. For Example the ACT Acceptance Test reports a bad PIT Timer (8254) since it Checks the correctness of the timer with some loop of instructions from the CPU. The BIOS of this machine consists of 4 2764 EPROMS and it therefore 32Kbyte long. So far the Intro, Now I wan't to disassemble the BIOS with the checks to build a version that's capable to run on a V30. Why? Just for fun... I've now looking for available 8086 emulators to load end step trough the BIOS code while looking what happens there (I'm not a x86 guy at all). Found two emulators on the Net (emu8086 and I8086emu) both both of them aren't capable to load a binary file as BIOS and step trough it. The emu8086 has'nt any capability to load the code in that are that I want f000:f800 until the end of the 1MB, at least I found no way to do this an dgot no answer to my question to the author and the 2nd one wich runs on Windows and Linux (FreeBSD to) as long as they are 32BIT OS's seems to support not more than 64KB Code in the last available release. So the final question is: Does someone know wo a software that can do that? Kind Regards and a merry Christmas, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741