diff --git a/grc/misc_utils/gsm_trx_burst_if.xml b/grc/misc_utils/gsm_trx_burst_if.xml index d3dab5c..252cf6a 100644 --- a/grc/misc_utils/gsm_trx_burst_if.xml +++ b/grc/misc_utils/gsm_trx_burst_if.xml @@ -32,32 +32,15 @@ - OsmoTRX like UDP interface for external applications. + OsmoTRX like UDP burst interface for external applications. - There are three UDP sockets: CLCK, CTRL and DATA. - Give a base port B (5700 by default), the SCH clock - interface is at port P=B. The TRX-side control interface - is on port P=B+100+1 and the data interface is on an odd - numbered port P=B+100+2. + There are two UDP connections, where each message carries + one radio burst with header. Give a base port B (5700 by default). + One connection at port P=B+100+2 is used for sending received bursts + to an external application. Another one at port P=B+2 is used to + obtain to be transmitted bursts. - Indications on the SCH Clock Interface (CLCK) - The SCH clock interface is output only (from the radio). - CLOCK gives the current value of the BTS clock to - be used by external applications. The indications are - sent whenever a transmission packet arrives that is too - late or too early. - - Commands on Control Interface (CTRL) - The control interface uses a command-response protocol. - Commands are NULL-terminated ASCII strings. Each command - has a corresponding response. This interface isn't handled - by this particular block, and should be implemented outside. - - Messages on the Data Interface - Messages on the data interface carry one radio burst per - UDP message. - - Received Data Burst: + Received burst format: 1 byte timeslot index 4 bytes GSM frame number, big endian 1 byte RSSI in -dBm @@ -66,7 +49,7 @@ 148 bytes soft symbol estimates, 0 -> definite "0", 255 -> definite "1" - Transmit Data Burst: + To be transmitted burst format: 1 byte timeslot index 4 bytes GSM frame number, big endian 1 byte transmit level wrt ARFCN max, -dB (attenuation)