diff options
Diffstat (limited to 'src/target/firmware/board/compal_e86/rffe_dualband_e86.c')
-rw-r--r-- | src/target/firmware/board/compal_e86/rffe_dualband_e86.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/src/target/firmware/board/compal_e86/rffe_dualband_e86.c b/src/target/firmware/board/compal_e86/rffe_dualband_e86.c index 4ad85dcd..c6dccd3d 100644 --- a/src/target/firmware/board/compal_e86/rffe_dualband_e86.c +++ b/src/target/firmware/board/compal_e86/rffe_dualband_e86.c @@ -48,10 +48,30 @@ void rffe_mode(enum gsm_band band, int tx) tsp_act_update(tspact); } -/* Returns RF wiring */ +/* + * Each given Mot C1xx phone is made either for 900+1800 MHz, in which + * case only the DCS Rx port is connected, or for 850+1900 MHz, in which + * case only the PCS Rx port is connected. Here we tell the TRF6151 driver + * that both DCS and PCS ports are connected, so that the same binary + * build can be used on both EU-band and US-band C1xx phones. + * + * If you are using your phone the way it was meant to be used, i.e., + * listening to EGSM and DCS downlinks only with EU-band phones or + * listening to GSM850 and PCS downlinks only with US-band phones, then + * the same standard binary build will work on both: the TRF6151 driver + * will use the DCS Rx port when trying to receive DCS downlink or the + * PCS Rx port when trying to receive PCS downlink, and everything will + * just work. However, if you are interested in using OsmocomBB for + * various hacking purposes (its original and primary intended use) + * and you need to tune your phone's TRF6151 receiver out of spec or + * at least outside of the DCS/PCS Rx SAW filter's legitimate passband + * (or if you have changed or removed that SAW filter), then you need + * to change the following rffe_get_rx_ports() function to match your + * specific hw version, i.e., PORT_DCS1800 only or PORT_PCS1900 only. + */ uint32_t rffe_get_rx_ports(void) { - return (1 << PORT_LO) | (1 << PORT_DCS1800); + return (1 << PORT_LO) | (1 << PORT_DCS1800) | (1 << PORT_PCS1900); } uint32_t rffe_get_tx_ports(void) |