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The USRP™ Hardware Driver Repository
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e320: Ensure consistent sequencing when powering on/off GPSDO #756

Open draeman-synoptic opened 4 weeks ago

draeman-synoptic commented 4 weeks ago

When powering up the GPSDO, ensure the GPS_3V3 rail is up before taking the GPSDO out of reset. When powering down the GPS_3V3 rail, ensure I/O signals to GPSDO are driven low so it isn't backfed power through control pins.

Description

It's worth noting that this PR doesn't address a known problem, but rather is an improvement in behavior I noted when I was troubleshooting an unrelated GPSDO issue.

Which devices/areas does this affect?

Affects MPM control of GPS power state on USRP E320 radios.

Testing Done

Confirmed that E320 generates GPS fixes and data, confirmed that "e320_bist gpsdo" runs as expected on the radio, confirmed that GPSDO can be powered on and powered off as expected.

Checklist