Slightly OT:Serial port and Hyperterminal

This is more of a PC question but also has to do with controls so I thought you guys might have seen this problem in the past. I have an application where my PC is talking to a laser head. It started to periodically lockup comms and not read the product. After some troubleshooting on the phone with the vendor we traced the problem to the PC itself. Using Hyperterminal I was able to connect to the laser from my laptop using a USB to Serial adapter. I then took the same adapter and it worked fine on the PC, so I ordered a new serial card for the PC. I put the new card in this morning and I still have the same problem. I can connect fine with the adapter but not with the internal card. When using hyperterminal, if I type the command 'R' I get a response from the laser using the adapter. But when plugged into the internal card hyperterminal will not even echo the typed characters. I am using the same terminal settings for both com ports and I have even tried using diffent port numbers with no luck. If I turn on local echo I see the characters typed but no response.

Any ideas would be helpful, I can't call the vendor until later as they are on west coast. I am able to run but want to use the internal card as it was designed so I can free up my adapter.

Thanks guys

If you are getting the same results with two different serial cards then I would suspect that it is a problem with the device driver for the serial card. You might try removing the driver and re-installing it.

I did try that, but maybe I did not fully uninstall driver when I did. I will try again.

Please define what laser you are using.
Omron uses cable specific interface cables.

regards,
james

Check the RS232 addressing. I suspect Com 1 and 2 are active in CMOS setup. This can happen if the CMOS battery is bad, and somebody reloaded defaults.

James, I am using a Hermary LRS-50 laser head. I know the cable setup is correct as we have been using the way it is for years.


Keith, would that cause a problem even if we are using COM 3 for the card and COM 4 for the USB adapter?

can you connect/type from the PC to HyperTerminal? ...

if not ...

just a guess - but check to make sure that the new internal card has its "jumpers" (if any) or DIP switches (if any) set correctly ...

and ...

that the PC setup has the proper "address" entered for the internal card ... something like D000 or C004 (just as examples) ...

also ...

make sure that there are no "conflicts" between various cards in the PC ... IRQ settings etc. ...

basic idea: make sure that the PC card can talk to HyperTerminal before you hook the PC and the other device together ...

Mark,

if you are using com 4 for the adapter and it works, I would try com 4 on the card and match the settings.

I have not used this brand of lasers before, but Omron is picky once the units are set up in regards to communications with the lasers / displays I have worked with.
james

Mark Snodgrass said:

Keith, would that cause a problem even if we are using COM 3 for the card and COM 4 for the USB adapter?

Click to expand...

No. Sometimes there's an IRQ conflict, but that's rare.
If you're letting Windows do the assignments, then IRQ shouldn't be a problem. Later versions of Windows assign different IRQ's, and will tell you about conflicts if you set them manually.

Addressing:
3F8, IRQ 4
2F8, IRQ 3
3E8, IRQ 4
2E8, IRQ 3

Hyperterminal is a great test. If your version doesn't have it, download an older version from the Internet. It's two files, and will run with later versions of Windows. Follow instructions here.

Check the handshaking settings in the on board serial port. My guess would be that they should be set to no handshaking but will default to hardware handshaking.