adccommunitymod (AutomationDirect) asked a question.
Created Date: October 30,2015
Created By: aphend
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I have been unsuccessfully trying to communicate non-sequence ASCII strings via RS-232 from a D0-DCM communication module in a DL-06. My PLC firmware is at 2.6 and the D0-DCM firmware is at 1.2. I am running DirectSoft 5.3. I can see that the option card is found under PLC- >Configure IO, and I can set it up properly in PLC-Setup- >D0-DCM. When I power up the PLC, the Tx/Rx LED's for each port on the D0-DCM, all light up briefly. The small example program I am running simply issues an AIN command and shifts the data into a waiting V memory location when complete. This program WILL work fine with the CPU's onboard port 2 but will NOT work with the DCM port 2. When using the DCM's port 2, the AIN command remains in the busy state and never fires its complete signal. Another interesting observation is that the port 2 Rx LED on the DCM never flickers when sending the ASCII strings. The AIN command is configure to look for a carriage return (0D Hex) on a variable length string. I have also tried fixed length strings and they do not work. During setup, I 've made sure the D0-DCM's slot ID is correct and that the V memory locations are accessible. The COM port setup is also identical to how I setup the working CPU's port 2. I have also tried shifting the DCM to all slot locations. I'm using HyperTerminal to send the test ASCII strings. Again, this works for the onboard port 2 using the same cable. Here is a link to the example program I am working with... Program EP-COM-008 from http://support.automationdirect.com/examples.html#com Any insight would be greatly appreciated
Created Date: October 30,2015
Created by: aphend
As a work around, I setup the D0-DCM for K-Sequence and used it for my HMI which worked fine, so I know the DCM is operational. Doing so allows me to use the PLC's onboard port 2 for Non-Sequence ASCII, which also works fine.
FRUSTRATING!
Created Date: October 30,2015
Created by: Do-more PE
I am not sure what to tell you. I tried it here yesterday when the tech asked if I knew of anything out of the ordinary that would prevent it from working. It works fine for me using the example as-is from the website.
The only thing I can think of is that on the Non-sequence setup for the port it asks for a memory address at the bottom of the screen. The default address needs to be changed to one that has 64 words of contiguous free memory available to it. (I just noticed that this is not stated in the manual. I will put in a request to get it changed.)
Created Date: October 30,2015
Created by: franji1
Also, make sure you have the right slot number for an 06. If you are used to 205 or 405 slot numbering, the first slot is slot "0 ". But in an 06, slot 0 is the built-in I/O, hence the first slot in an 06 is slot "1 ". You might just have an OBOB (what we affectionately call an Off-By-One-Bug).
Created Date: October 30,2015
Created by: aphend
I am not sure what to tell you. I tried it here yesterday when the tech asked if I knew of anything out of the ordinary that would prevent it from working. It works fine for me using the example as-is from the website.
The only thing I can think of is that on the Non-sequence setup for the port it asks for a memory address at the bottom of the screen. The default address needs to be changed to one that has 64 words of contiguous free memory available to it. (I just noticed that this is not stated in the manual. I will put in a request to get it changed.)
Thanks for replying! You say you used the program as-is, but you did change the AIN parameters to use DCM correct? I got the program to work as is off the website too when I was plugged into port 2 of the PLC (CPU).
I did also read about the large block of contiguous memory required, but not how much, or if any special preparations need to made for this memory. I used V10000 so the module had V10001 to V17777.
There was also some info I came across about using the slot's special registers for busy and error. I did integrate the special register for COM busy at the AIN rung, without success.
Created Date: October 30,2015
Created by: aphend
Also, make sure you have the right slot number for an 06. If you are used to 205 or 405 slot numbering, the first slot is slot "0 ". But in an 06, slot 0 is the built-in I/O, hence the first slot in an 06 is slot "1 ". You might just have an OBOB (what we affectionately call an Off-By-One-Bug).
Thanks for the reply. I do have the correct slot identified knowing "slot " 0 is the CPU.
Created Date: October 30,2015
Created by: aphend
I made up my own adapter so I could use an EA-2CBL-1 cable to connect to port 2. Is there anything odd about the pinout of port 2 on the DCM? I simply crossed pins 2 and 3 and grounded pin 7. Again, this cable arrangement works with the PLC's onboard port 2.
Created Date: October 30,2015
Created by: Do-more PE
Try tying the RTX and CTS lines together on the cable. It should be the Dark Green and Dark blue wires.
Created Date: October 30,2015
Created by: aphend
Try tying the RTX and CTS lines together on the cable. It should be the Dark Green and Dark blue wires.
Well, I have to say - great idea! Putting a loopback between RTS/CTS on the PC side took care of the issue. I can now read and write ASCII in non-sequence mode. Thank You so much!
Andrew
Created Date: October 30,2015
Created by: Do-more PE
You are very welcome. I wish I had thought of it yesterday when you called.
Created Date: October 30,2015
Created by: ControlsGuy
So if the solution was RTS jumped to CTS on the PC end, why did the same port setup with the same cable work on the other PLC port? That seems odd.