> There's a 1-sheet here on page 816. > http://bitsavers.informatik.uni-stuttgar...Peripherals.pdf > > Also, pretty sure I got the actual datasheet around here somewhere. Me and Fujitsu > part numbers MB86*, MB87*, MB88* and MB89* go a ways back. ICMiner.com claims to have > it but is having trouble loading it right now. > > But as you say (and according to the Fujitsu databook): you don't need it if you > understand the Intel 8237A. > > - Stiletto
Thanks for the input Got a copy of the 8237A datasheet already.
Seems the Comm Boards IO space is actually addressed by the lower 8 bits only I know that is some undocumented "feature" but how do I map these in MAME
some init stuff (leaving 0x60 in A) 1st io read (from 0x08) from IO 0x6008 to A some calculations (leaving previous read in A) 2nd io read (from 0x08) from IO 0x0008 to A
Anyway the Registers seem to map like this: IO **00 - **1F - DLC Registers IO **20 - **2F - DMA Registers
There are some elusive writes to **40 and **60 too, but I don't have a clue what they actually are. The value also gets written to internal memory. I'll check the board layout later.
Index 
Flat 
Re: Help emulating the model1 comm board
Reply
Help emulating the model1 comm board
