> > Date: Mon, 15 Jun 2015 19:42:42 -0400 > From: Michael Thompson <michael.99.thomp...@gmail.com> > To: cctech <cct...@classiccmp.org> > > The M452 creates a 220 Hz clock for the TTY transmitter and a 880 Hz clock > for the TTY receiver. > The M405 for the DP12-B serial port generated a clock that is 16x the baud > rate which is then divided by an M216 module. > > Michael Thompson > > Just to prolong this discussion...
The PDP-12 came to us with an M452 for the 110 baud TTY console and a home-made adjustable baud rate module for the second serial port. The adjustable baud rate generator was made by the original user of the system in the early 80s, and is just a crystal, rotary switch and a Fairchild 4702. I ordered a replacement Intersil IM4702 so we can repair the module. The original owner doesn't remember ever having an M405 for the second serial port. -- Michael Thompson
