assembler, disassembler for Intel 8089?

Chuck Guzis cclist at
Fri Sep 25 13:22:05 CDT 2015

On 09/25/2015 09:56 AM, Al Kossow wrote:

> What I/O board are you trying to figure out, Eric? A bunch of
> different manufacturers early Multibus Winchester controller boards
> used them.

The 8089 was a good idea but badly timed and terribly underpowered.  2 
channels of DMA, while a plain old 8257/8237 could give you 4.  When the 
80186 was being sampled, it too, had 2 channels of 20 bit DMA on-chip, 
so why fool with another chip.  In the meantime, RAM prices were headed 
lower, so having private RAM for an I/O device (e.g. hard disk) made DMA 
less important.

Good idea, wrong timing.  When I approached "Fast Eddie" our Intel sales 
guy, he gave me a bunch of documentation on the 8089 and told me that it 
wasn't worth looking into for a design.  This was about 1980.


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