diaelecj07 Posted July 11, 2012 Report Posted July 11, 2012 I have a serial communication card (QJ71C24N) that seems to be disconnecting. Periodically, my laser-marker will stop receiving data from the communication card. When the problem occurs, I check the system monitor via GX Dev. and it says the module has been disconnected. Replacing the card has not helped. Has anyone seen this or can anyone offer any advice while I troubleshoot it? Thanks QJ71OK.bmp QJ71NG.bmp Quote
Gambit Posted July 11, 2012 Report Posted July 11, 2012 Have you replaced the Backplane or put the card in another slot? Quote
diaelecj07 Posted July 11, 2012 Author Report Posted July 11, 2012 No and Yes. I do not have access to another Backplane yet. I moved the card over to the next slot and the same problem occurred. So far, we have: Replaced the QJ71C24N card Changed card slots Replaced the CPU Thanks in advance. Quote
Crossbow Posted July 12, 2012 Report Posted July 12, 2012 Are you sure the card is disconnecting? Are you sure it's not just a communication error being flagged? Is this a high vibration environment? Are you relying on the plastic latch to hold the card in place or is it screwed into the backplane? Quote
diaelecj07 Posted July 13, 2012 Author Report Posted July 13, 2012 The card is not physically disconnecting. The LED display list on the card stays lit and displays no error. There is no indication of an error with this current card... However the previous card gave an error 1414. There is no vibration. The card is screwed into the backplane. Quote
kaare_t Posted July 17, 2012 Report Posted July 17, 2012 In the picture it seems to me that the module is disconnected from the rack itself (you can see that the software cannot access the name of the card just above "32pt"). Try changing the backplane.... Quote
diaelecj07 Posted July 17, 2012 Author Report Posted July 17, 2012 (edited) I installed a new backplane and a new expansion cable this morning. The module 'disconnected' within an hour... The presence of the card seems to be detected... but information about the card and transmitted data seems to be lost. I wonder what else could cause this... thanks Edited July 17, 2012 by diaelecj07 Quote
diaelecj07 Posted July 20, 2012 Author Report Posted July 20, 2012 This may or may not be related, but the serial com. card gave an warning earlier which it has not done before 7F42 - Transmit watchdog timer (timer 2) time-out occurred - Check if DTR control, etc. interrupted transmission The info about the card in system monitor did not disappear this time... Could there possibly be any relation? Quote
kaare_t Posted July 20, 2012 Report Posted July 20, 2012 Try another computer, or use a different USB->RS232 converter... Quote
diaelecj07 Posted August 9, 2012 Author Report Posted August 9, 2012 Just an update: I used GX Config to change the settings in the "Ch1 Transmission Control and Others Monitor/Test" - Retransmission time - from 'Do Not Retransmit' to 'Retransmit' - Transmission Monitor Time (timer 2) - from 0708 to 0000 I still haven't found/fixed the problem, but this has stopped the card from disconnecting and going into error. Quote
kaare_t Posted August 12, 2012 Report Posted August 12, 2012 Not really sure what happens, but here's a wild guess: You are transmitting data, but the received data to the C24 is not processed correctly, and the receive buffer is not cleared for each faulty receive operation. This causes the buffer to fill up. Could you try to write a small function that clears the receive buffers (there's a buffer memory in the module for flushing the input buffer)? I have a feeling that this could be the problem. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.