TN788B Multimedia Voice Conditioner circuit pack is used in conjunction
with the TN787F/G multimedia interface circuit pack to provide
service circuit functionality for the MMCH feature. This feature
provides both voice and multimedia data service between multimedia
The TN788B vintage is µ-Law only. The TN788B vintage 2 or
later is A-Law and µ-Law.
TN788B is the audio processor for the Px64 multimedia conference
TN788B contains 8 digital signal processors; 4 for encoding and
4 for decoding. Each encoder/decoder pair is assigned to a Px64
endpoint to process its audio channel.
to and from the endpoint's audio is by way of a TN787F/G multimedia
interface port. This connection is through the TDM bus timeslots.
of the 8 digital signal processors communicate with the main on-board
processor through 8 individual Dual Port Random Access Memory
Read Only Memory (ROM) is available on this circuit pack; the
DPRAM is used for program download.