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Diffstat (limited to 'grc/trx_interface/gsm_trx.xml')
| -rw-r--r-- | grc/trx_interface/gsm_trx.xml | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/grc/trx_interface/gsm_trx.xml b/grc/trx_interface/gsm_trx.xml new file mode 100644 index 0000000..cf882ef --- /dev/null +++ b/grc/trx_interface/gsm_trx.xml @@ -0,0 +1,68 @@ +<?xml version="1.0"?> +<block> + <name>TRX interface</name> + <key>grgsm_trx_interface</key> + <import>import grgsm</import> + <make>grgsm.trx($remote_addr, $base_port)</make> + + <param> + <name>base_port</name> + <key>base_port</key> + <value>5700</value> + <type>string</type> + </param> + + <param> + <name>remote_addr</name> + <key>remote_addr</key> + <value>127.0.0.1</value> + <type>string</type> + </param> + + <sink> + <name>bursts</name> + <type>message</type> + </sink> + + <doc> + OsmoTRX like UDP 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. + + 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: + 1 byte timeslot index + 4 bytes GSM frame number, big endian + 1 byte RSSI in -dBm + 2 bytes correlator timing offset in 1/256 symbol steps, + 2's-comp, big endian + 148 bytes soft symbol estimates, 0 -> definite "0", + 255 -> definite "1" + + Transmit Data Burst: + 1 byte timeslot index + 4 bytes GSM frame number, big endian + 1 byte transmit level wrt ARFCN max, -dB (attenuation) + 148 bytes output symbol values, 0 & 1 + </doc> +</block> |