PDP-12 Restoration at the RICM (tony duell)

Michael Thompson michael.99.thompson at gmail.com
Sun Jun 14 16:42:58 CDT 2015

> Date: Sun, 14 Jun 2015 15:25:08 +0000
> From: tony duell <ard at p850ug1.demon.co.uk>
> To: "General Discussion: On-Topic Posts" <cctech at classiccmp.org>
> Subject: RE: PDP-12 Restoration at the RICM
> > Warren made an Arduino based programmable baud rate generator that works
> > for both serial ports. After some debugging, it works nicely.
> I am sorry, but I find that obscene!. To use more components than the rest
> of the machine
> (probably) just for the baud rate clock is ridiculous. IMHO if you are
> going to modify a
> vintage machine, particularly one as rare as a PDP12, you should use the
> components
> that were available at the time. It's not as if a programmable buad rate
> generator is hard
> to make from TTL either. In fact given the Arduino thing needed 'some
> debugging' it might
> well have taken less time to do it in hardware.
> -tony

Tony, thank you for your offer to supply replacement M452 Variable Clock
modules for the console. We already have one jumpered for 110 baud for the
Teletype. The other two M452 modules should be jumpered for 9600 baud and
38400 baud. The second serial port uses a M405 Crystal Clock module with a
different pinout and clock outputs than the M452. We don't have any of
these modules, so the three that we need should be jumpered for 110 baud,
9600 baud, and 38400 baud. The shipping address for the RICM is on the WWW

Michael Thompson

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