Pinout for SED9421 - test-drb@ccmp.vtda.org

25 Nov 2005

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Subject: Re: Pinout for SED9421
   From: shoppa_classiccmp at trailing-edge.com (Tim Shoppa)
   Date: Fri, 25 Nov 2005 16:56:16 -0500
     To: cctalk at classiccmp.org

"Peter C. Wallace" <pcw at mesanet.com> wrote:

  On Fri, 25 Nov 2005, woodelf wrote:

  Allison wrote:

  Either that a Dflop(74LS74), hex D-latch(74LS174)
and 32x4 prom(74LS288).

   Just for the heck of it,  got a schematic and a prom listing?
 Did anybody ever use a serial chip and a data separater
 rather than a floppy disk controler? 
 Heathkit did with their H89 hard sectored floppy controller....

 Peter Wallace

Also Ohio Scientific, I think that was with an async UART? (Don't
know for sure, but I do know the best way to get the correct information
is to post incorrect information!)

Tim. 
I think the part they used was an USART as in async, bisync, and HDLC/.x25
kinda thing.

Allison