robot giving me silent treatment

[trubleshtr]

I am trying to com. with much older robots. I have built cables, and re-built and re-checked cables between computer and controller. I still get same error code, which according to my manual means either, parity error,Over run error, or framing error.

Now, I understand the parity error , and tried changing to all other parity options systematically, = no good.
What I dont understand is what an over run or framing error is exactly?
Could someone shed some light on this for me please? Then I may know which direction to go.

Many thanks.

[cncwhiz]

What is your baud rate set at? I had the same problem on some 6m controls and it worked with a slower baud rate?

[Al_The_Man]

Originally Posted by trubleshtr I still get same error code, which according to my manual means either, parity error,Over run error, or framing error. Now, I understand the parity error , and tried changing to all other parity options systematically, = no good. .

I am not sure what the problem is you have but an understanding of what the 'frame' is, is a help. The RS232 is a asynchronous method of transmission , which means the recieving device locks on to the the incoming bit stream when it sees a start bit, and when it sees what it thinks is a stop bit it assumes that is then end of a 'frame' , therefore both send and recieve devices have to be in tune as to the data word set up, i.e. start bit, data, parity, stop bit(s) etc. and of course, baud rate.
If for instance one is set to 6 data bits and the other 8 data bits, then a frame error will probabally result.
Al

[trubleshtr]

books say it should be 4800bps,even parity,7 bits 1 stop bit,basic protocal

i set my com 1 port accordingly, built cables...and re-built cables...
I also had to convert from a 25db connector to 9 pin on my computer (that's how old this technology is) I went to a web site a followed their diagram for converting 25 pin to 9 pin connector. So Now I have 9 pin on laptop, 25 pin on old controller. I thought I had made cable wrong, so I left off the connectors and just push the cable pins into the according spots on the recieving connectors (so I could move them arround if need be) I think the TXD and RXT signals are wrong in the manual?
Is there a cheap serial interface detector to verify what signal is where?
thanks

[cncwhiz]

If you have a newer pc the you should go into your advanved setting for you com port and turn off FiFo. There should be a tab for this.

[trubleshtr]

I 'm starting to wonder if someone has messed with dip switches. I have no info on them, manufacteur will no longer support this system either, looking like i might have to gut the controlls to more modern system. I would really like to make sure I have exhausted all avenues before pulling the trigger on changing control hardware/software.

[trubleshtr]

Thanks for the advice, I will try a more modern laptop, as the one I am using is a dianasour. Maybe hyperterminal will be more successful.

[Al_The_Man]

Hyperterminal is a pain in the A***, use the freebee from http://www.cadem.com before that, They also have all the pin outs for RS232 25 & 9 pin 'D'.
Al

[trubleshtr]

thanks Al, I will try the freebee first.

[Jay C]

Originally Posted by trubleshtr books say it should be 4800bps,even parity,7 bits 1 stop bit,basic protocal i set my com 1 port accordingly, built cables...and re-built cables... I also had to convert from a 25db connector to 9 pin on my computer (that's how old this technology is) I went to a web site a followed their diagram for converting 25 pin to 9 pin connector. So Now I have 9 pin on laptop, 25 pin on old controller. I thought I had made cable wrong, so I left off the connectors and just push the cable pins into the according spots on the recieving connectors (so I could move them arround if need be) I think the TXD and RXT signals are wrong in the manual? Is there a cheap serial interface detector to verify what signal is where? thanks

Serial cables only require 3 lines. Send, receive and ground. Connect pin 2 of host 1 to pin 3 of host 2, pin 3 of host 1 to pin 2 of host 2, and ground to ground. Is the robot supposed to output a startup message or diagnostic when you power it up or push a button? If so, then set your connection up, press the button and see if anything (even gibberish) shows up in hyperterm. If you have an oscope, it will help you measure the frequency of the bits to help narrow down the baud.

Jay

[Al_The_Man]

Originally Posted by Jay C Serial cables only require 3 lines. Send, receive and ground.

Not strictly so if you want to use hardware handshake, this when you use a null-modem cable.
Al

[Jay C]

Ok, is it safe to assume that the equipment he is using requires hardware handshaking? If so, that complicates things

Jay