V25 pinout?

[Tony Duell]

> > I just looked, and V.25 explicitly refers to the V.24 pinout. V.25 (and 
> > V.25bis and V.25ter) only specify procedures user over the v.24 circuit in 
> > automatic dialling scenarios (when to raise/lower which signals and a 
> > DTE-DCE command/response format) V.25ter is the familiar AT command set.
> 
> Hmmm....
> 
> 
> I have an instrument here (an HPIB extender) with 2 DB25's on the back. 
> One is marked 'RS232 V24' and is clearly a normal-ish serial port to 
> connect to a modem. The other is for an autodialer and is marked 'RS336 
> V25' (I think that's the right RS number, maybe RS339). I don't think 

It's actually RS366 (that will teach me to post without the device in 
front of me), which seems to be a standard for the interface to an 
autodialer.

>From waht I can determine, it uses 'RS232 levels', and transfers a nybble 
at a time in parallel to dial a phone number (digits are encoded in BCD, 
the other 6 combinations are used for things like #, * I guess). I found 
a pinout for that on the web, and amazingly the pins used in the HPIB 
extender would agree with that :-)

-tony