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ahuat

usb to rs232

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Dear all, Mostly new generation of laptops do not have a serial port, what i need to know is, if it is possible to use a third party usb to rs232 converter to communicate between laptop and cpu. i tried use a third party usb to rs232 converter to connect between laptop and cj1m cpu but no success. thank you all.

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I am currently using a cheap USB->RS232 converter I bought on Ebay from Hong Kong, without any problems! I use it to connect to a CJ1M CPU13 and a CJ1G CPU45

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There are many threads regarding USB to RS32 converters on the technical forums. Some work some of the time, some work most of the time, some don't work at all. There are many factors that seem to figure in to the issue. Most of the feedback indicates the Keyspan HS-19 is pretty reliable. I have had good luck with it most of the time. When I got my new laptop, I did make sure it had a real serial port. Hope this will help.

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also, in Windows, did you go to "control Panel" -> "system" -> device manager -> ports -> and pick the USB to serial adapter listed, and make sure the port settings match the port settings of the PLC. Usually the baud rate is 9600 on the converter, and 115200 on the Omron PLC, so make it match the 115200. If you plug the converter into a different USB port, windows will re-assign it into a different number of com port, so once you connect, always use the same USB port. Start bits, data bits, stop bits, flow control must match as well. Use the Omron default settings in both places and it should work. Omron tech support is great at helping you get your settings right. Call your supplier for the number.

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Hello ahuat, I'm surprised that no-one has mentioned the purpose made Omron CS1W-CIF31 USB to serial converter. Made by Omron, it is guaranteed to work with their PLCs. I have also used Belkin USB / Serial adapter without any problems.

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Last time I looked HP/Compaq still had some models with real serial ports.

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Dear All, Thanks for your replies. i just did some experiments and want to share with you all, I use cheap usb serial converter, i get it with only around 8 dollars. First i connect to CJ1M to my laptop ( SONY Vaio ) with my usual serial cable, length is around 3 mtr. Doesn't work at all. Then i try to connect the usb serial converter via my Desktop, and it worked!! Then i change my normal serial cable with better quality cable and shorter, and connect cpu to my laptop ....surprisingly it works!! The only problem is everytime i disconnect my laptop from CPU, the blue screen appears. My conclusions are : 1. USB in desktop has more "power" to do the signal convert ( i'm have no information about this ) 2. Better quality cable gives better performance. 3. Shorter cable give better performance. I hope can help others Regards ahuat

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I also get the dreaded windows blue screen when I disconnect and I am using the OMRON CS1W-CFI31 adapter with the most recent driver which I believe is V1.20 and a Compaq nx9600 laptop. I have tried the adapter with a different brand of laptop and it works fine and no blue screen even when you yank the adapter out of the port while you are online . Live and learn!

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after numerous problems with converters (even Omron).... we decided to use PCMCIA serial ports: advantages: 1. behaves the same as built is hardware 2. you typically have 2 ports 3. you keep having usb slots open for mouse, mass-storage,.... Beegee

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Beegee, After reading your post from yesterday, I did a bit of research and have concluded that PCMCIA-RS232 is the way to go. Thanks for your input on the subject. This is an extract from Quatech's site referring to the card which confirms what you said in your first point of advantages:

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I've used various USB adapters with no problems (unless it's a really cheap and nasty one). I mostly use the Omron CIF31 with a home made serial cable. You do need to stick to the same USB port all the time as it'll load a set of drivers each time you plug it in to a different one and this can cause issues. Could also be an OS problem. New laptops are shipping with Vista which I'd avoid like the plague - stick to XP pro.

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