PDP 11/23+ progress
ajp166 at bellatlantic.net
Mon Jun 13 15:17:13 CDT 2005
>Subject: Re: PDP 11/23+ progress
> From: "Jim Beacon" <jim at g1jbg.co.uk>
> Date: Mon, 13 Jun 2005 20:38:43 +0100
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>> >I'm now getting garbage on the terminal, but have yet to figure out which
>> >setting I've got wrong!
>> >Please see our website the " Vintage Communication Pages" at
>> Likely baud rate. Try 4800n1.
>I have the terminal set 4800n1, and the CPU switch and jumper settings seem
>to agree (what I can see), though there must be something that is not
> The confusing bit (for me ), is that there are two RX wires, RCV+ and RCV-,
>what is the convention for using these, with say a VT320? is one of them
>normally connected to earth? At th moment, I have the RCV+ connected to the
>terminals TXD, and RCV- is earthed (how I found the system) - is this
RS422/RS423 I'd have to look now. I bet someone answers before I
find may notes. Obviously you don't have the DEC connector pannel
or cables or this would be sorted out for you.
Suffice to say if the COMMON (RS232 pin 1 and 7 are not corosponding
with The right inputs the result is either inverted data or RX hears TX.
More information about the cctalk