GSM modem interfacing with Propeller

fliq50

Hi all...
i want to ask...
can this Serial to Propeller Connection (http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/SerialtoPropeller.pdf) interfacing with GSM modem? can it communicate each other?

sorry for my poor english... thanks...

Tubular

If the GSM modem supports RS232 (some are TTL voltage levels instead of RS232), it should work by swapping pins 2 and 3 at the 9 pin D connector.

This is because the circuit you link to is designed to connect the Prop to a PC, which is "DTE" or Data Terminal Equipment. A modem is likely to be "DCE" or Data CommunicationEquipment, which means you need to swap over the pairs (like a Null modem does).

I'm not sure about the reset signal (from Pin 4 on the ) - it depends on your application.

fliq50

thanks Tubular... really appreciate it...
i will try for my project.

fliq50

thanks the information I got here... really useful...

I already communicate the prob and the gsm modem. So the problem I face is to sent message to the gsm modem. The problem start with the quotation mark ( " ). How to call the quotation mark in the propeller? I try and test but seem goes wrong.. the Parallax Serial Terminal shows

AT+CMGS=S=15551236789S=

TRY TEST POWER,

AT

there also goes wrong with the control_z program to sent the message in the gsm modem...

thanks again

this is my test program by reference the Jay Kickliter program...

CON
_CLKMODE = xtal1 + pll4x
_XINFREQ = 5_000_000
DELAY = 0.5
CONTROL_Z = 26
QUOTATION_MARK = 34

OBJ
serial : "Parallax Serial Terminal"

VAR
long stack[10]
byte text

DAT
phone_send_sms_command byte "AT+CMGS=", 0 ' First part of command, the rest is phone number in quotes
at_command byte "AT", 0 ' Phone should return "OK"
cr_nl byte 13, 10, 0 ' Carrige return + newline
phone_number byte "15551236789", 0
message byte "TRY TEST POWER", 0


PUB SendSMS(recipient_phone_number, message_text)
serial.StartRxTx(31, 30, 0, 115200)

serial.str(@phone_send_sms_command) ' Send sms preamble, AT+CMGS=
serial.str(QUOTATION_MARK) ' Send a "
serial.str(@phone_number) ' Send phone number string, eg. 15551236789
serial.str(QUOTATION_MARK) ' Send a "
serial.str(@cr_nl) ' Send carrige return and newline control characters
waitcnt(clkfreq/2 + cnt) ' Wait for phone to process command
serial.str(@message) ' Send message string
serial.str(CONTROL_Z) ' Send Control-Z character
serial.str(@cr_nl) ' Send carrige return and newline control characters
waitcnt(clkfreq/2 + cnt) ' Make sure phone has enough time to process command before next
serial.str(@at_command) ' Send another AT for good measure
serial.str(@cr_nl) ' Send carrige return, and newline control characters
waitcnt(clkfreq/2 + cnt) ' Wait for phone to process command

Tubular

try this
Serial.str(string(QUOTATION_MARK))
etc

That seems to work when I do something similar

cheers
tubular

fliq50

thanks Tubular....
U save my day...
it really work...
now I'm getting excited with the propeller...

Tubular

Great! There is so much that can be done with the prop

The GSM modules can be frustrating; so much power, but you have to know what commands to use and in which order.

fliq50 wrote: »

thanks Tubular....
U save my day...
it really work...
now I'm getting excited with the propeller...

fliq50

Ok... I'm done with the sending messege. How about receiving message? and use the message that I sent to turn off pin 5?
I'm use the at-command cmgr=1. So, when the gsm modem replay to the propeller, how do I know which memory in Propeller it store the message that I sent? and how to call it?

Thanks in advance..