Download MULTIPROTOCOL SOFTWARE USER'S MANUAL

II-20
DIALOG PROCEDURE BETWEEN THE CARD AND THE PC
The "TX Cnt j" counter indirectly tells the programmer the usage rate of the transmit buffers
associated with channel j. Each time a write request is made (see the BTRAN command), a
1024-byte transmit buffer is occupied, whatever the size of the information frame to send.
The transmit counter is then decreased by 1024. Once the transmitted frame is acknowledged,
this counter is incremented by 1024 and the associated buffer is freed. This counter returns to
its maximum value (the width of the look-ahead window*1024) once all the buffers have been
freed.
The card allocates K transmit and receive buffers when the PROTO command is executed,
where K is the width of the look-ahead window.
Special case for an X25 channel
The “Rx Cnt j” and “Tx Cnt j” counters are not meaningful in X25. However, they provide
information on the occupation rate of the buffers at the LAPB software layer. Specific
counters for the buffer occupation rate for each logical channel are located in the data zone
(See the chapter entitled “The Command Interpreter in X25 mode” section VI.1).
MULTIPROTOCOL SOFTWARE USER’S MANUAL (DTUS016) - REV. B.03 JAN. 5, 1998