Annals of OS and network history

From: Joe <rigdonj_at_intellistar.net>
Date: Wed Mar 11 08:30:44 1998

At 11:24 PM 3/10/98 +0000, you wrote:
>>
>>
>> <> More recently, Intel designed the 8089 I/O co-processor as part
>> <> of the 8086 family. It had an instruction set optimized for I/O
>> <> functions.
>>
>> And not so recently starting with the AT and all after the keyboard
>> interface chip is a slave cpu (8041a or 8042).
>
>Well, my 8089 data sheet is copyright 1980,

  Hey, you did RTFB!

  Joe :-)

so I'd put that chip before
>the PC/AT. This chip was used as the DMA controller in the original
>Apricot PC, BTW.
>
>The 8089 is really a very fancy DMA controller with a limited processing
>ability as well. There are AND/OR/NOT/ADD instructions (although no XOR,
>no SUB and no shifts/rotates). It looks to have been a pretty nice chip -
>pity it never caught on. It's a lot nicer than the 8237 + page register
>kludge used on the PC.
>
>
>> Allison
>
>-tony
>
>
Received on Wed Mar 11 1998 - 08:30:44 GMT