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All things pertaining to wireless and RF links
By geometrixeng
#187500
Hey Everybody,

I am currently using a MG2639 Cellular Shield with a PIC24F host.

I am able to send AT commands from the PIC24F host to the MG2639, and I have confirmed this with my signal analyzer. The transmit pin on the PIC24F host idles HIGH and works as expected (this is how the UART is configured).

But I have noticed that the TX signal from the MG2639 to the RX pin on the PIC24F idles LOW, and I receive nothing whatsoever back from the MG2639. Even if I received nothing back from the MG2639, SHOULDN'T THE TX PIN ON THE MG2639 IDLE HIGH????

TIA,
--NEAL