diff options
| -rw-r--r-- | mpm/python/usrp_mpm/cores/tdc_sync.py | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/mpm/python/usrp_mpm/cores/tdc_sync.py b/mpm/python/usrp_mpm/cores/tdc_sync.py index cc5158525..cc9981205 100644 --- a/mpm/python/usrp_mpm/cores/tdc_sync.py +++ b/mpm/python/usrp_mpm/cores/tdc_sync.py @@ -131,12 +131,14 @@ class ClockSynchronizer(object): self.log.trace("Running clock synchronization...") - # Reset and disable TDC, disable PPS crossing, and enable re-runs. Confirm the - # core is in reset and PPS is cleared. - self.poke32(self.TDC_CONTROL, 0x2121) + # Reset and disable TDC, and enable re-runs. Confirm the core is in + # reset and PPS is cleared. Do not disable the PPS crossing. + self.poke32(self.TDC_CONTROL, 0x0121) reset_status = self.peek32(self.TDC_STATUS) & 0xFF if reset_status != 0x01: - self.log.error("TDC Failed to Reset! Status: 0x{:x}".format(reset_status)) + self.log.error("TDC Failed to Reset! Status: 0x{:x}".format( + reset_status + )) raise RuntimeError("TDC Failed to reset.") # Set the RSP and RTC values based on the Radio Clock and Reference Clock @@ -164,11 +166,10 @@ class ClockSynchronizer(object): if reset_status != 0x00: self.log.error( "TDC Reset Failed to Clear! " \ - "Check that your clocks are toggling. Status: 0x{:x}".format(reset_status) - ) + "Check that your clocks are toggling. Status: 0x{:x}".format( + reset_status + )) raise RuntimeError("TDC Reset Failed.") - - self.log.trace("Enabling the TDC") # Enable the TDC. # As long as PPS is actually a PPS, this doesn't have to happen "synchronously" @@ -185,7 +186,7 @@ class ClockSynchronizer(object): raise RuntimeError("Failed to capture PPS.") self.log.trace("PPS Captured!") - + meas_clk_freq = 170.542641116e6 measure_offset = lambda: self.read_tdc_meas( 1/meas_clk_freq, 1/self.ref_clk_freq, 1/self.radio_clk_freq @@ -232,7 +233,11 @@ class ClockSynchronizer(object): time.sleep(0.5) if not self.lmk.check_plls_locked(): raise RuntimeError("LMK PLLs lost lock during clock synchronization!") - self.poke32(self.TDC_CONTROL, 0x1000) # Re-enable PPS + # After shifting the clocks, we enable the PPS crossing from the + # RefClk into the SampleClk domain. We never explicitly turn off the + # crossing from this point forward, even if we re-run this routine. + self.poke32(self.TDC_CONTROL, 0x1000) + return distance_to_target |