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Rs232 to USB cable problem

  newface 17:31 28 Mar 2009

I bought a hand held scanner which had a female 9 pin connector. My laptop only had a 15 pin rs232 connector. As I had spare usb ports I got a USB cable that had a male 9 pin attachment at one end. I also downloaded some drivers for HL-340. When the cable is attached it shows up as com4 usb-serial ch340 usb2.0-ser!. When I run the software associated with the scanner, a light on it flashes, but nothing else happens.
Does anyone have any idea if I am using the combination of cables etc?

  mgmcc 22:25 28 Mar 2009

If the port on the Laptop is an RS232 Serial port, are you sure it isn't 25-pin male?

You should be able to get a 25-pin female to 9-pin male RS232 Serial Cable to connect the laptop and scanner directly. Have a look at this page click here

  newface 14:29 30 Mar 2009

mgmcc thanks for your response. However, last night it occured to me that I probably need a null modem adapter to go between the USB cable and the serial port on the laptop.
I have just ordered one today, and will post again if it solves problem.

  woodchip 15:09 30 Mar 2009

Make sure Com Ports are Enabled in BIOS

  mgmcc 15:11 30 Mar 2009

OK, but a Null Modem adapter/cable would normally be used when connecting two computers directly via their Serial Ports, rather than when connecting a peripheral to a PC. However, let's hope it does sort the problem.

  T0SH 15:57 30 Mar 2009

The 15 pin female D type connector on a laptop will be the VGA output for an external monitor or a projector, not a serial port

Cheers HC

  newface 16:38 30 Mar 2009

Many thanks to all of you who have taken the time to post a reponse. I will take on board all of your comments and post the outcome here when the adapter arrives.

  newface 11:41 02 Apr 2009

Ok, here's the situation as it stands. The null modem 9 pin arrived yesterday. I have just attached it and tried to use the scanner. My hardware configuration shows that there is now a COM6, but when I run the software to use the scanner I get a message to check whether the scanner is attached or powered on.

Has anyone got any ideas?

  mgmcc 13:59 02 Apr 2009

If the scanner hardware has installed on COM6, is there anything in the software to configure the serial port to use?

  newface 15:02 02 Apr 2009

Hello mgmcc. Yes the software seems to detect which of the USB ports the cable is connected into. I can move the cable into any of the 3 USB slots and the system allocates it as COM4, 5 or 6 accordingly.
I have also noticed that when the USb to 9d pin cable is connected to the cable that came with the scanner, a light on the scanner will flash once when I ttry to download. This does not happen when the null modem is attached in between them.
I hope that this makes sense to you.

  newface 16:39 02 Apr 2009

Hi Poitier, the reason I bought the null adapter was because the scanner was not working when attached via the USB port. I bought the adapter just in case there was some sort of mix up over the transmit / receive, but the problem seems to lie a little deeper. All the FAQ pages say that it is possible to attach this device via a USB slot even though it was origionally designed to attach via COM1.

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