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enigma
- 11th June 2016, 15:35
Hi All

I'm running a GL865 and it would be useful to know the network registration status by monitoring the status LED. When the module is not registered the status pin is low for around 1 second then high for around 0.5 seconds. When registered the pin is low for around 3 seconds and high for around 0.3 seconds. Any suggestions as to the best way to determine if the pin remains low for say 1.5 seconds. I'm working on the fact that if it is low for that period it must be in a registered state, there's no need to time to 3 seconds so long as the period exceeds the unregistered value.
Cheers Pete

HenrikOlsson
- 11th June 2016, 17:27
As usual there are many ways and as usual it depends on what other things your program is doing and what hardware resources you have available - in the PIC and outside.

When not registred the dutycycle of the signal is ~33% and when registred it's ~10%.
Run it thru a low pass filter and sample it with the ADC or use a comparator. Yes, the frequency is really low so you'll need a "large" filter but so what. It's not going to jump on and off the network several times per minute (hopefully).

Or, if your mainloop is somewhat constant in its execution time then simply poll the input every iteration and work out the time.

With that said, doesn't it have some kind of statusregister, with a bit indiciating network status, that you can read?

/Henrik.

enigma
- 13th June 2016, 13:37
Hi Henrik
Yes there is an AT command but its not that consistent. I`m looking at monitoring this from the main look, unfortunately I`ve already got the hardware so I cant easily add in the integrator components. I loop every 1 second so I`ll try polling and see what I get.
Cheers Pete