15 Jan
2004
15 Jan
'04
6:15 a.m.
Jay West wrote:
I have a system that does an "autobaud" when
you hit return to log in. If I
hook up a VT220, it works at 7/1/E, 8/1/N, 7/1/O, etc. etc. no problem. If I
hookup a Televideo 950, hitting return gets no response at all. This is NOT
a DTE vs. DCE problem, because the televideo does work with the same system
on a different type of serial port.
I was thinking something might be brain damaged with parity
generation/checking on this terminal. Is this a known issue of TV950's?
About the only way I can find out whats going on is to dig out my datascope
and see the start data & stop bits between the two when hitting return and
see what is different.
Any thoughts?
Jay West
I've had problems in the past with voltage levels on RS-232.
One device runs -12/+12V, the other 0/+5V, and they refused
to talk bi-directionally. Putting in a homemade level shifter
(forced the 0/+5 to -9/+9) made it work.
I think this may have been Televideo widgets to a Vax/3100, iirc.