On Thu, Jun 16, 2016 at 11:55:53AM -0400, James Knott via talk wrote: > Data General Nova & Eclipse computers had a choice of AC power or > various clock rates derived from a crystal. The crystal wasn't all that > accurate, but normally AC is.
It would be pretty accurate for sure. > The Data General Nova predates microprocessors. It was first build > around 1969, IIRC. The Eclipse, while a later generation, used the same > basic I/O board, which included the RTC circuits, along with serial port > for the console and ports for the paper tape punch & reader. Yeah that would be old enough to such a thing. > Incidentally, one thing I did was modify those boards from 20 mA current > loop to RS-232 for the console and also replaced the fixed crystal > serial port clock (you had to change the crystal to change speeds) with > a baud rate generator chip that used a colour burst crystal to generate > a variety of baud rates. With the 2 mods, those boards moved from 110 > b/s Teletypes, to 9600 b/s CRT terminals for the console. That's a nice improvement. -- Len Sorensen --- Talk Mailing List [email protected] https://gtalug.org/mailman/listinfo/talk
