Can anyone give me the "table" (or a URL to) of ABCD bit values in T1
> signalling. Everywhere I Googled refers to these but none give the
> meaning of each of the bit combinations. I'm particularly interested
> in "off-hook/onhook" states.
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May be instructive and useful ...
P.S. ---- I know you said "T1", but just as FYI
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has some good info on various flavors [or should I say, flavours :-)] of E1 R2 signalling, and the accompanying signalling bits if anyone is interested.