Robafe

Serial Port issue

6 posts in this topic

Sorry its long !!

I am recieving text from a GSM modem for text msg Send and receive (SMS)

works ok but would be better if I could make use of the start code and end code.

This way I could cut down on all the crap that is received when a text arrives.

I get this 

CMTI: "SM",0

I have it stored into D80 and I have that trigger a TXD that sends

AT+CMGRD=0 and that tells the GSM to send the msg (The 0 is the current msg in memory)

------ The problem is that there is Carriage  Return and Line Feeds in the received msg ----      AS below

((AT+CMGRD=0
+CMGRD: "REC UNREAD","+19028991212","","22/10/20,16:57:54-16"
 Hello this is the msg 

OK))

When the PLC sees the carriage return it stops receiving data. And I have no start code or end code setup. (I am using characters received)

The way around this is to set a high  character count in the RXD (More than the actual msg (More than the msg length)  

The main issue with that is I get garbage in as the msg gets bigger. Its unreliable.

I clear the port after each receive and that helps but still get the odd garbage. (Never get garbage when connected to a terminal prg).

Any Ideas????

ps

Even the Start Code is unreliable as it will start receiving a few characters late.

Rob

 

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Couldn't you setup your end code as "))"?

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39 minutes ago, photovoltaic said:

Couldn't you setup your end code as "))"?

Just one ")" I mean, which would be a value of 29 (hex)

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It stops receiving as soon as it sees any CR LF Never gets to the end code (port 2)

Also 

Port 1 is setup to receive 14 chars. A phone # and location code

9025552565A001 when I send it over and over it will change on of the #s Like instead of 902 it will show 912 

Basically the same issue as I have with port 2

I wired the connector up from an example on this site I will find it and past it here.

I have had a lot of issues with these omrons. 

2 CP1L and one will NOT connect to my NB the other connects works ok

Modem  PLC

           2 - 3

           3 - 2

           5 - 9

    (4,6)    (4,5)

    (7,8)     (7,8)

 

Rob

 

Edited by Robafe

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Is there a wiring diagram for hardware flow control? for the serial ports????

Rob

 

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On 10/21/2022 at 3:45 PM, Robafe said:

Is there a wiring diagram for hardware flow control? for the serial ports????

Rob

 

 

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