Modem Auto Answer-Hanging for 1 min...

**Ioannis** · - 17th August 2005, 20:24

Luciano, thank you for your extensive reply. The corrections were made, ok.

As for the main problem, it has nothing to do with the external device. It's something related to the sub handling from PBP. Look at the following response taken from the Terminal program suggested earlier:

ATE0
ATV0 <-- at this point I am sending a 0 from the terminal
ats0=2 <-- response is as expected from the program
ATX3 <-- again as expected
AT<00> <-- upto this point, were the command freezes!
<-- then after a minute the <00> appears and execution
continues normally!

AT+CMGF=1
ATS37=9
ATS40=2

So the problem is inside the UART of the PIC as it may look...

Ioannis

**Bruce** · - 17th August 2005, 21:59

If you disconnect the modem, and just monitor serial data the PIC is sending, what results do you get?

**Luciano** · - 17th August 2005, 23:01

Hello,

My theory was wrong.

Bruce in the post #13 there is no modem connected.

The post #13 as I understand it:

The PIC sends "ATE0" to the RX pin of the PC. (The terminal program of the PC shows ATE0).

The PIC sends "ATV0" to the RX pin of the PC. (The terminal program of the PC shows ATV0).
Ioannis types "0" in the terminal program of the PC and the PIC gets this byte
otherwise no further AT commands are sent by the PIC.

The PIC sends "ats0=2" to the RX pin of the PC. (The terminal program of the PC shows ats0=2).

The PIC sends "ATX3" to the RX pin of the PC. (The terminal program of the PC shows ATX3).

The PIC sends "AT&K0" to the RX pin of the PC, but the PC terminal program shows only
AT and after a minute in addition to AT the PC receives also <00>. So after a minute
on the PC screen you will see AT<00> and the execution of the program continues normally
in the PIC. (So the PIC does not successfully send AT&K0 to the PC).

Ioannis please confirm that.

Luciano

**Ioannis** · - 18th August 2005, 13:13

Luciano yes. You are right. This is exactly the case. Bruce, sorry, in #13 I did not clearly stated that the device was disconnected.

Please also note that, if all the 3 Hserin commands are joined as one then there is NO problem in the transmitted string! (I do not know if there is other problem in some other subroutine though...)

So, as I can conclude up to this moment, there must be some difficulty from PBP to work with many and some long sub routines.

Also, if the subrounines are transfered from the top to the bottom then this problem disappears! (Others from other sub's are appearing then...)

Black Magic or what?

Ioannis

**Ioannis** · - 19th August 2005, 15:11

If I Copy the part of the program with the studied problem to a new fresh program, with no other commands, subroutines or whatsoever, then it runs normally!!

Ioannis

**Bruce** · - 19th August 2005, 15:16

Hi Ioannis,

If you're using the MPASM assembler, can you post the .COD file? If using the PM assembler, then post the .HEX file. I can run it through MPLAB, and see if I can find where it's hanging. I'm curious.