We observe some strange #GSMAD behaviour. Antenna detection circuitry is impemented according to the Telit Antenna Detection Application Note. We periodically send AT#GSMAD=3,0,1,5 and get the following result codes:
1. first call always returns 1 (short circuited to ground) irrespectively of antenna real state,
2. 10 KOhm resistor (imitating antenna) gives 0 (connected) – as it should be,
3. open connector gives sometimes 3 (open) – which is correct, but sometimes 1 (short circuited to ground),
4. sometimes #GSMAD doesn’t return anything (looks like it hangs) and sometimes it returns ERROR.
Firmware version is 10.00.002.
Can you give explanation / workaround suggestions for this unstable behaviour?
can you send your schematic? unfortunately here I can’t see your problem.
#GSMAD works forever.
Here’s the relevant part of schematic. We use GPIO4 as GPIO(A) and GPIO5 as GPIO(B).
Hi Roman, can you try the latest FW version?
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