diff --git a/executables/nr-ru.c b/executables/nr-ru.c
index b2eb4710163237bf2b46f02a564c87eeade9b0d8..7e2ddb06458e518b9a436f154d149dd9f21dcedc 100644
--- a/executables/nr-ru.c
+++ b/executables/nr-ru.c
@@ -754,6 +754,10 @@ void tx_rf(RU_t *ru,int frame,int slot, uint64_t timestamp) {
nextslot_type == NR_UPLINK_SLOT) {
flags = 3; // end of burst
}
+
+ // the beam index is written in bits 8-10 of the flags
+ // the following choice cycles through the beams every slot, starting with beam 3
+ flags |= ((3+slot)&7)<<8;
VCD_SIGNAL_DUMPER_DUMP_VARIABLE_BY_NAME( VCD_SIGNAL_DUMPER_VARIABLES_TRX_WRITE_FLAGS, flags );
VCD_SIGNAL_DUMPER_DUMP_VARIABLE_BY_NAME( VCD_SIGNAL_DUMPER_VARIABLES_FRAME_NUMBER_TX0_RU, frame );
diff --git a/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp b/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
index e2418bcb76238e1ef96c121a0dba1ec4229aa785..f3395d9c93a496b824cc69323054bcfaec9f8bf3 100644
--- a/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
+++ b/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
@@ -276,14 +276,17 @@ static int trx_usrp_start(openair0_device *device) {
// setup GPIO for TDD, GPIO(4) = ATR_RX
//set data direction register (DDR) to output
- s->usrp->set_gpio_attr("FP0", "DDR", 0x7f, 0x7f);
- //set control register to ATR
- s->usrp->set_gpio_attr("FP0", "CTRL", 0x7f,0x7f);
+ s->usrp->set_gpio_attr("FP0", "DDR", 0xfff, 0xfff);
+ //set lower 7 bits to be controlled automatically by ATR (the rest 5 bits are controlled manually)
+ s->usrp->set_gpio_attr("FP0", "CTRL", 0x7f,0xfff);
//set pins 4 (RX_TX_Switch) and 6 (Shutdown PA) to 1 when the radio is only receiving (ATR_RX)
s->usrp->set_gpio_attr("FP0", "ATR_RX", (1<<4)|(1<<6), 0x7f);
// set pin 5 (Shutdown LNA) to 1 when the radio is transmitting and receiveing (ATR_XX)
// (we use full duplex here, because our RX is on all the time - this might need to change later)
s->usrp->set_gpio_attr("FP0", "ATR_XX", (1<<5), 0x7f);
+ // set the output pins to 0
+ s->usrp->set_gpio_attr("FP0", "OUT", 3<<7, 0xf80);
+
// init recv and send streaming
uhd::stream_cmd_t cmd(uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS);
LOG_I(HW,"Time in secs now: %llu \n", s->usrp->get_time_now().to_ticks(s->sample_rate));
@@ -404,10 +407,19 @@ static int trx_usrp_write_recplay(openair0_device *device, openair0_timestamp ti
@param antenna_id index of the antenna if the device has multiple antennas
@param flags flags must be set to TRUE if timestamp parameter needs to be applied
*/
-static int trx_usrp_write(openair0_device *device, openair0_timestamp timestamp, void **buff, int nsamps, int cc, int flags) {
+static int trx_usrp_write(openair0_device *device,
+ openair0_timestamp timestamp,
+ void **buff,
+ int nsamps,
+ int cc,
+ int flags) {
int ret=0;
usrp_state_t *s = (usrp_state_t *)device->priv;
int nsamps2; // aligned to upper 32 or 16 byte boundary
+
+ int flags_lsb = flags&0xff;
+ int flags_msb = (flags>>8)&0xff;
+
#if defined(__x86_64) || defined(__i386__)
#ifdef __AVX2__
nsamps2 = (nsamps+7)>>3;
@@ -441,40 +453,48 @@ static int trx_usrp_write(openair0_device *device, openair0_timestamp timestamp,
boolean_t first_packet_state=false,last_packet_state=false;
- if (flags == 2) { // start of burst
+ if (flags_lsb == 2) { // start of burst
// s->tx_md.start_of_burst = true;
// s->tx_md.end_of_burst = false;
first_packet_state = true;
last_packet_state = false;
- } else if (flags == 3) { // end of burst
+ } else if (flags_lsb == 3) { // end of burst
//s->tx_md.start_of_burst = false;
//s->tx_md.end_of_burst = true;
first_packet_state = false;
last_packet_state = true;
- } else if (flags == 4) { // start and end
- // s->tx_md.start_of_burst = true;
- // s->tx_md.end_of_burst = true;
+ } else if (flags_lsb == 4) { // start and end
+ // s->tx_md.start_of_burst = true;
+ // s->tx_md.end_of_burst = true;
first_packet_state = true;
last_packet_state = true;
- } else if (flags==1) { // middle of burst
- // s->tx_md.start_of_burst = false;
- // s->tx_md.end_of_burst = false;
+ } else if (flags_lsb==1) { // middle of burst
+ // s->tx_md.start_of_burst = false;
+ // s->tx_md.end_of_burst = false;
first_packet_state = false;
last_packet_state = false;
- } else if (flags==10) { // fail safe mode
- // s->tx_md.has_time_spec = false;
- // s->tx_md.start_of_burst = false;
- // s->tx_md.end_of_burst = true;
- first_packet_state = false;
- last_packet_state = true;
+ }
+ else if (flags_lsb==10) { // fail safe mode
+ // s->tx_md.has_time_spec = false;
+ // s->tx_md.start_of_burst = false;
+ // s->tx_md.end_of_burst = true;
+ first_packet_state = false;
+ last_packet_state = true;
}
+ // push GPIO bits 7-9 from flags_msb
+ int gpio789=(flags_msb&7)<<7;
+
s->tx_md.has_time_spec = true;
s->tx_md.start_of_burst = (s->tx_count==0) ? true : first_packet_state;
s->tx_md.end_of_burst = last_packet_state;
s->tx_md.time_spec = uhd::time_spec_t::from_ticks(timestamp, s->sample_rate);
s->tx_count++;
+ s->usrp->set_command_time(s->tx_md.time_spec);
+ s->usrp->set_gpio_attr("FP0", "OUT", gpio789, 0xfff);
+ s->usrp->clear_command_time();
+
if (cc>1) {
std::vector<void *> buff_ptrs;