Suggestions for USB-serial conversion

[rwy34ils]

I'm using a serial port card that plugs into my PCM card slot. Not sure if laptop makers are still providing these or not. It has worked flawlessly on everything over the past couple years. Cost a couple hundred dollars.

One of the problems with the USB to serial adapters is that the PC may assign some ridiculous COM number to it, for example COM 17. When you fire up your programming software you may find that it won't recognise any com ports higher than COM 4 or COM 8.

 

[Mickey]

One of the problems with the USB to serial adapters is that the PC may assign some ridiculous COM number to it, for example COM 17. When you fire up your programming software you may find that it won't recognize any com ports higher than COM 4 or COM 8.

That can be changed. See picture below. Go to device manager and change it the the port you like. The next time you plug it in to the same USB port it will take the com # you set it at the last time you plugged it in. The trick is to remember which USB port you used last time.

 

[rwy34ils]

That can be changed. See picture below. Go to device manager and change it the the port you like. The next time you plug it in to the same USB port it will take the com # you set it at the last time you plugged it in. The trick is to remember which USB port you used last time.

My first post and I've learned something already! Thanks!

 

[Mickey]

My first post and I've learned something already! Thanks!

And Welcome to the forum.

 

[kbradray]

What am I missing. I have the recommended Keyspan HS-19 just in today. I have installed hardware and software and everything looks good on the Keyspan cable (COM 3) I have not been able to go online with my ML1100 yet. I am changing the com port in the driver configuration of Linx, but cannot see the processor. Help Please
Ken

 

[Mickey]

The Ml1100's serial port can be configured for DF1,DH485,Modbus,ASCII or shut-off. If you have the offline file take a look at its port configuration and set RSLinx's driver to match. If the port is set up for DH485 the Keyspan will not work. You will need a 1747-UIC ( usb to DH485 converter) What cable are you using?

Or see post below.

http://www.plctalk.net/qanda/showpost.php?p=317008&postcount=4

 

[kbradray]

Thanks Mickey

I discovered my problem in linx. Thanks for your reply. I am using the Keyspan that Ken recommended earlier in this thread. I had my device configured incorrectly in linx.

Thanks again for all who help here. I find more answers here than anywhere else.

 

[Dravik]

One thing i've noted is turning off Power Saving for the USB ports helps a lot with keeping the USB-Serial adapters happy.

 

[panic mode]

just out of curiosity, did anyone try the 4-port unit USA-49W?

 

[lbg_dk]

Hi for my new Dell i did buy a ExpressCard/34 with a RS232 serielport.

But the first one did not work that was internal a ExpressCard to usb and then usb to RS232 :-(

So look for one with a 16C950 comp. UART that will work

Just for the record i did buy this one http://danbit.dk/produkter/0902.phtml EXP3-1RS232

 

[Currently]

Another gotcha to be aware of is that some PLC's do not like USB/Serial cables to be connected to USB Hubs.

The cable has to be the only item on the port.

 

[morganjack]

DataLink has an external USB to DH+ converter that replaces the 1784-PKTX and 1784-PCMK functionality. They have also just released an AB Ethernet RSLINX driver to DH+ www.protocolconverter.com