briellelaw
commented
2 years ago For Oct launch (and likely any upcoming launches in 2021) we will not be utilizing the SBDRING feature. This would require a major refactoring of our bbb_satellite_listener code. In the interest of time, this may or may not be revisited in the future.
Right now we successfully check the ring alert status with 'AT-CRISX', but this just tells us the most recent Type of alert that was received (telephony vs SBD) not if there is a pending ring alert.
We actually need to poll for the SBDRING announcement sent from the rockblock. However, the announcement is only sent when the rockblock is in 'command mode' I think this requires us to be sending an AT command at the time. I think we have to send an SBDRB command prior to polling for SBDRING, because the announcement is sent to the last known location of the rockblock https://docs.rockblock.rock7.com/docs/faqs
Potential solution is to create another function that sends a simple AT command and just waits until the SBDRING announcement is received.
Another solution is to make use of the 'timestamp' -which is a hex value representing the Iridium system time (# 90ms frames from the last epoch). But based on experimentation, this value doesn't seem to change - at least within a 5 second polling interval. https://www.rock7.com/downloads/ATC_Iridium_ISU_AT_Command_Reference_MAN0009_v5.pdf