[comp.sys.atari.8bit] ATR 8500

chasm@killer.DALLAS.TX.US (Charles Marslett) (06/28/89)

In article <245@hhb.UUCP>, bvk@hhb.UUCP (Brett Kuehner) writes:
> Also, what is an ATR 8500? I just saw it mentioned in the new MyDOS posts,
> and I'd never heard of it before.

The ATR8500 is a smaller version of the ATR8000 that differed primarily in
that it had (if I remember correctly) a DMA controller and an SIO chip on
it rather than the acre of TTL that the 8000 used to access the disk and
serial ports.  As a side effect, it coul handle much higher data rates when
multiple channel I/O was going on, and it had much higher RS232 baud rate
accuracy and throughput (one interrupt per character, vs. several per bit
with the 8000's software UARTs).

The major problem is that SWP came out with it about the time they had lost
the ability to provide any software support -- so it was over a year before
Robert Morris and I got the RS-232 driver running, and I do not know of any
attempt to use it as an SCSI disk controller.  The MIO and Supra parallel
bus HD interfaced pretty well killed that market anyway (since they are
inherently so much faster).

> 		Thanks,
> 			Brett
> --
> Brett Kuehner, HHB Systems, Mawah, NJ
> ...!princeton!hhb!bvk
> bvk%hhb@princeton.EDU

===========================================================================
Charles Marslett
STB Systems, Inc.  <== Apply all standard disclaimers
Wordmark Systems   <== No disclaimers required -- that's just me
chasm@killer.dallas.tx.us