snewton@ (Steve Newton) (10/22/89)
In article <133@euteal.ele.tue.nl> blitter@ele.tue.nl (Paul Derks) writes: >In <1989Oct17.234017.18698@lsuc.on.ca> jim@lsuc.on.ca (Jim Mercer) writes: ->I have been trying to upgrade from my 4.77 Mhz XT to a turbo for a year now. ->finally, i got the speed i wanted. i managed to swap an old Altos 580 i had ->for an 80186 motherboard that is supposed to be XT compatible. >Be prepared for some wonderfull problems and get yourself an 80186 data book. However, it is not that bad for MS-DOS programs (keep it for dac-easy,etc). Most programs do not require knowledge about the DMA or Timer. Some do like to insert a 'key monitor' and thus issue a End of Interupt. It is a 'compatible' but it will be useful to have a better clone until you are able to port/convert/patch programs to RUN ONLY ON THAT MACHINE!! >totally not hardware compatible with the PC's peripherals. Interrupt vectors, >hardware registers are all in the wrong places. Perhaps the board is DOS >compatible on the BIOS level but certainly not at the hardware level. >You will have to change the kernel considerably. : Do what I did- disassemble the ROM (debug: uFFFF:0000 and many t&p's 8:) Look for a out ax to FF02--This establishes a table base for all other internal chip ports. Let's form a mailing list of those lucky to have 286 speed without a MMU (the 186)