SEROUT2 to GSM Modem

[tommyers]

Hi,

I am using a GM862-QUAD GSM modem from Roundsolutions, via AT commands generated from a PIC16F74 running picbasic pro.

here is my simplified code:

'Initialising Variables
TXPIN VAR PORTD.3 'TX PIN
RXPIN VAR PORTD.2 'RX PIN

RL1 VAR PORTB.2 'RELAY OUTPUT
STAT VAR PORTB.1 'STATUS LED

BAUD CON 396 'BAUD RATE = 2400 N 8 1

RELAYFLAG VAR BYTE

ADCON1 = 6

DEFINE OCS 4

START:

pause 3000 ' start up delay

'first command is to set the text mode
SEROUT2 TXPIN, BAUD, ["AT+CMGF=1",13] '-- answer 'OK'

PAUSE 2000 ' 2 second delay to allow modem more than enough
' time to respond

'text setup
SEROUT2 TXPIN, BAUD, ["AT+CSMP=17,167,0,0",13] '-- answer 'OK'

PAUSE 2000 ' allow modem to respond

'send a message without saving
SEROUT2 TXPIN, BAUD, ["AT+CMGS=",34,"xxxxxxxxxxx",34,13] '--answer '>'
PAUSE 500 'short delay

' add the body of the message ending with ctrl-z
SEROUT2 TXPIN, BAUD, ["WORK",26]

PAUSE 500 'short delay
HIGH STAT 'completion indicator


STOPLABEL:

' stay here when complete
GOTO STOPLABEL

The code started life out listening for the responses before continuing - but as I wasn't having much luck with it I stripped all this out!

Ok, so whats happening or not happening.

I have setup hyperterminal to send out these exact same commands and this works fine. I also have the luxary of a serial data analyser so I can monitor the data being sent and received. When send these commands via hyperterminal the modem sends the code to the number (note xxxxxxxxxxx - for privacy!) and all is well.

I then disconnect hyperterminal and instead connect my PIC circuit and let the code above run. I monitor the results on my serial analyser and the commands send to and received from the GSM modem look indentical! BUT THE MESSAGE AINT SENT! I cannot fathom what is going wrong!?

both the code and hardware seem to function because I get the same serial data - apart from hyperterm generated works and PIC generated doesnt!?

Can anyone advise.

Thank you and Regards

Tom