cctech Digest, Vol 123, Issue 3 - test-drb@ccmp.vtda.org

3 Nov 2013

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 From: David Riley <fraveydank at gmail.com>
 Date: Sat, 2 Nov 2013 21:07:35 -0400
 Subject: Re: Looking for a MicroController Recommedation
 On Nov 2, 2013, at 17:13, John Wilson <wilson at dbit.com> wrote:

 You could probably pair it with a small CPLD or FPGA to help
 with the shifting (if, as Chuck pointed out, the SPI hardware won't
 do the trick). That could add as little as $5 to your BOM, even in
 single-unit quantities.

 - Dave

I used an Actel SmartFusion FPGA to connect to the I/O bus in a PDP-8 and
emulate a paper tape reader. The time sensitive bus interface logic was
programmed into the FPGA. The built in ARM Cortex M3 runs uC Linux with a
device driver to talk to the FPGA logic and a small application to supply
the paper tape image.

You could do the same and put the disk controller logic in the FPGA and
have an application running under Linux to supply the read/write data
functions. You could use the same disk image that the emulators use and
store it in flash.

-- 
Michael Thompson