Attention is currently required from: Hoernchen, laforge, tempest, tnt, ttsou. Hello Hoernchen, Jenkins Builder, laforge, tnt, ttsou, I'd like you to reexamine a change. Please visit https://gerrit.osmocom.org/c/osmo-trx/+/41231?usp=email to look at the new patch set (#2). The following approvals got outdated and were removed: Code-Review+1 by Hoernchen, Code-Review+1 by laforge Change subject: trx: Fix tx/rx-sps 4 for USRP1 devices ...................................................................... trx: Fix tx/rx-sps 4 for USRP1 devices The existing code sets the pingOffset variable to -7231(269 - 7500) with tx-sps = 4. The (apparent) correct value for pingOffset for tx/rx-sps 4 is 272. While I'm not completely sure how this patch works to fix the increased sps value, my theory is that the original OpenBTS TRX only supported a split sps setup(tx-sps=4, rx_sps=1 for sps=4), which created differing decimation rates between Tx and Rx on the board. In this case, apparently you needed to account for an advance in the timestamp for a correct output. With tx_sps == rx_sps, the decimation/sample rates will be the same, and(I guess) this advance doesn't need to be accounted for. Also changed a line in the initialization of the Rx end of the USRP device to use the correct decimation rate when tx/rx-sps == 4. Since osmo-trx won't allow nonequal values for tx-sps and rx-sps, I commented out the logic that selected pingOffset based on sps. I left it visible in the file for reference however. Tested & working on the URAN-1, a USRP1 clone designed for GSM. Change-Id: I3b08c23a3e7d4a226cd23b9fe42558f596a63257 --- M Transceiver52M/device/usrp1/USRPDevice.cpp 1 file changed, 8 insertions(+), 7 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-trx refs/changes/31/41231/2 -- To view, visit https://gerrit.osmocom.org/c/osmo-trx/+/41231?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings?usp=email Gerrit-MessageType: newpatchset Gerrit-Project: osmo-trx Gerrit-Branch: master Gerrit-Change-Id: I3b08c23a3e7d4a226cd23b9fe42558f596a63257 Gerrit-Change-Number: 41231 Gerrit-PatchSet: 2 Gerrit-Owner: tempest <jackleea1b@gmail.com> Gerrit-Reviewer: Hoernchen <ewild@sysmocom.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: laforge <laforge@osmocom.org> Gerrit-Reviewer: tnt <tnt@246tNt.com> Gerrit-Reviewer: ttsou <tom@tsou.cc> Gerrit-CC: fixeria <vyanitskiy@sysmocom.de> Gerrit-CC: pespin <pespin@sysmocom.de> Gerrit-Attention: Hoernchen <ewild@sysmocom.de> Gerrit-Attention: laforge <laforge@osmocom.org> Gerrit-Attention: tempest <jackleea1b@gmail.com> Gerrit-Attention: tnt <tnt@246tNt.com> Gerrit-Attention: ttsou <tom@tsou.cc>