On 2017-Jun-14, at 11:33 AM, Noel Chiappa via cctalk wrote: >> From: Brent Hilpert > >> I don't expect anyone was making boards like this expecting to get the >> target timing from fixed/off-the-shelf component values > > Right, that comment was more directed to the discussion here about baud rate > variation. > >> There are two trimpots on the board, they could be one for each of the >> rate series and switch-selected > > No, the prints (1105_RevAH_EngrDrws_Jul76, page 71) shows there's only one RC > circuit associated with the UART. I don't know what the second trim-pot does > (I'm too lazy to look over the prints to find it :-).
Oh, regarding the two trimpots (as well as the 7493 divider) I was referring to the original-poster TRS-80 serial board, not the PDP11/05.
