DL06 D0-DCM receiving and sending ASCII strings problem.

[raghfrost]

Dear Gentlemen/Ladies,

I have a bit of a nut cracker here. I am using a Koyo DL06 and a D0-DCM (slot 4). I have some issues with the DCM module. I will try my best to describe the problem i am facing.
I tried setting up the DCM using ladder instructions but it just did not want to work instead i set it up via PLC->Setup ->D0-DCM its works partially.

I went to the automation direct and there was an example program that worked like a charm for the onboard CPU PORT2 i could send and receive ASCII strings.

when it came to receiving ASCII strings from DCM i could only receive but no send. I've used the AIN instruction and i have used internal relay C1 on rising edge to setup count everytime a transaction is complete. this works when i am receiving ASCII string from the CPU port2 but not from the DCM. What am i doing wrong?
I have attached the code used only to receive ASCII strings from the DCM.

I would sincerely appreciate help from you Gurus

Ragh

 

[ATU]

You might try posting on the AD website. I am not sure that ASCII communications are fully supported on that module yet.
http://forum.automationdirect.com/

If it is, make sure you have the latest firmware.

 

[raghfrost]

How do i check for the firmware?

 

[raghfrost]

I've Updated the firmware but it's still not behaving..

 

[icky812]

For both the D0-DCM and the PLC?

 

[raghfrost]

dang.. will do the plc tomorrow. how could I not think about the PLC!... thanks for the tip

 

[raghfrost]

I updated both the firmware but they are not working right... sometimes on occasion they work and sometimes they dont.. i am really stumped.

 

[icky812]

A couple of things to try.

1) After you do your processing on the string, toward the end of the program try adding a NO contact C1 and ACRB instruction to clear the receive buffer.

2) If #1 does not help, try adding a NC contact C0 into rung #2 to lock out the AIN while busy, until it is complete.


One last thought. What memory address did you use for the non-Sequence buffer on the D0-DCM when you set it up?

The buffer takes quite a bit of memory area that you need to be sure to reserve for it's use.

 

[cjh]

Yea, just to re iterate what Icky said:
Unless it is just too early in the morning and my coffee hasn't kicked in yet, it looks like you will always have C100 on (except for maybe 1 scan).
This will make the AIN stay on and you will not be able to send anything out of the port.

Do what he said and just manually control the AIN on and off. Be sure that the AIN is not on when you try to use the PRINT instruction.

 

[raghfrost]

I have rewritten the code trying to turn on AIN when either CPU Port 2 or DCM port 2 is only working.

CPU port 2 is receiving into V4000
AIN receiving buffer at V5000
then Moved to V5500

DCM Port 2 is receiving into V2000
AIN receiving Buffer at V3000
then Moved to V3500

I will keep you posted, i am trying to do what icky812 mentioned.
Thanks Gurus for lending me a hand.

 

[raghfrost]

The process is working now.. after trouble shooting all morning i realised that, the problem lied with the memory mapping (you were spot on icky812 ) and using the special relays SP116 and SP126 to alternate the AIN instruction. The special relay instructions were tipped by the good guys at automation direct Mr.Ken. Once again thank you for all your help folks. I sincerely appreciate it Ragh