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Transceiver52M: Update to UHD streamer interface 

This patch is long overdue and can now be merged after better understanding
of timestamp stability issues. UHD tick / timespec conversions were
generally used with the streamer interface, though these calls are actually
independent change sets. The combination would lead to internal rounding
errors and a timing drift most notably on B100 running at GSM symbol
rate multiples. There are no known issues, however, with the streamer code
itself.

The aforementioned issue was discovered in test code only, which was never
merged to mainline.

Signed-off-by: Thomas Tsou <tom@tsou.cc>
This commit is contained in:
Thomas Tsou 2013-04-05 15:11:35 -04:00
parent d734e2d634
commit b4cb4e23c0
2 changed files with 16 additions and 29 deletions
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43
Transceiver52M/UHDDevice.cpp
View File

@ -204,6 +204,8 @@ public:
private:
uhd::usrp::multi_usrp::sptr usrp_dev;
uhd::tx_streamer::sptr tx_stream;
uhd::rx_streamer::sptr rx_stream;
enum busType bus;
double desired_smpl_rt, actual_smpl_rt;
@ -310,16 +312,8 @@ void uhd_device::init_gains()
void uhd_device::set_ref_clk(bool ext_clk)
{
uhd::clock_config_t clk_cfg;
clk_cfg.pps_source = uhd::clock_config_t::PPS_SMA;
if (ext_clk)
clk_cfg.ref_source = uhd::clock_config_t::REF_SMA;
else
clk_cfg.ref_source = uhd::clock_config_t::REF_INT;
usrp_dev->set_clock_config(clk_cfg);
usrp_dev->set_clock_source("external");
return;
}
@ -451,10 +445,14 @@ bool uhd_device::open(const std::string &args)
#ifdef EXTREF
set_ref_clk(true);
#endif
// Create TX and RX streamers
uhd::stream_args_t stream_args("sc16");
tx_stream = usrp_dev->get_tx_stream(stream_args);
rx_stream = usrp_dev->get_rx_stream(stream_args);
// Number of samples per over-the-wire packet
tx_spp = usrp_dev->get_device()->get_max_send_samps_per_packet();
rx_spp = usrp_dev->get_device()->get_max_recv_samps_per_packet();
tx_spp = tx_stream->get_max_num_samps();
rx_spp = rx_stream->get_max_num_samps();
// Set rates
actual_smpl_rt = set_rates(desired_smpl_rt);
@ -488,14 +486,8 @@ bool uhd_device::flush_recv(size_t num_pkts)
timeout = .01;
for (size_t i = 0; i < num_pkts; i++) {
num_smpls = usrp_dev->get_device()->recv(
buff,
rx_spp,
md,
uhd::io_type_t::COMPLEX_INT16,
uhd::device::RECV_MODE_ONE_PACKET,
timeout);
num_smpls = rx_stream->recv(buff, rx_spp, md,
timeout, true);
if (!num_smpls) {
switch (md.error_code) {
case uhd::rx_metadata_t::ERROR_CODE_TIMEOUT:
@ -634,13 +626,12 @@ int uhd_device::readSamples(short *buf, int len, bool *overrun,
// Receive samples from the usrp until we have enough
while (rx_smpl_buf->avail_smpls(timestamp) < len) {
size_t num_smpls = usrp_dev->get_device()->recv(
size_t num_smpls = rx_stream->recv(
(void*)pkt_buf,
rx_spp,
metadata,
uhd::io_type_t::COMPLEX_INT16,
uhd::device::RECV_MODE_ONE_PACKET);
0.1,
true);
rx_pkt_cnt++;
// Check for errors
@ -718,11 +709,7 @@ int uhd_device::writeSamples(short *buf, int len, bool *underrun,
}
}
size_t num_smpls = usrp_dev->get_device()->send(buf,
len,
metadata,
uhd::io_type_t::COMPLEX_INT16,
uhd::device::SEND_MODE_FULL_BUFF);
size_t num_smpls = tx_stream->send(buf, len, metadata);
if (num_smpls != (unsigned) len) {
LOG(ALERT) << "UHD: Device send timed out";

2
configure.ac
View File

@ -98,7 +98,7 @@ AS_IF([test "x$with_usrp1" = "xyes"], [
])
AS_IF([test "x$with_uhd" = "xyes"],[
PKG_CHECK_MODULES(UHD, uhd >= 003.002.000)
PKG_CHECK_MODULES(UHD, uhd >= 003.004.000)
AC_DEFINE(USE_UHD, 1, Define to 1 if using UHD)
])