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All things pertaining to wireless and RF links
By gwassick
#198896
Looking for a little help.

I can use an Arduino Uno and the libraries to communicate with the Reader. But when I try to connect a FTDI cable to the board, without the arduino attached, I am not able to communicate with the board using the Universal Reader Assistant software. The FTDI cable is functional, I can loop TX to RX and see the characters come back. When I look at the RX and TX lines using a scope, as soon as a character is sent all I get is very high frequency noise on the serial port lines. I’ve tried several FTDI Cable, other serial to TTL cables, and a USB isolator on the FTDI Cable. Has anyone else seen this issue? Has anyone been able to use the reader with an FTDI Cable?

Thanks, Greg
By paulvha
#198907
I am using the M6E Nano with the CH340G and USB cable. I have had that issue as well. (on linux and windows with the URA). The M6E is (very) sensative to enough power, even if you set the TX and RX power to 500. Mine is normally powered by the USB cable. I have tried stronger power 5V supplies, but it did not really help. (maybe because of the 5V - 3.3V regulator in the CH340G) The only thing that works for me is to connect an extra charged battery (SR674361P : 3.7V/ 2000maH) to the on-board battery connector.
Alternatives:
In the URA you can try to connect first, lower the TX/RX power to 500 and try to read.
Another aspect to check/increase the USB power setting in Windows (there are enough articles on Internet for that).
Last but not least it could be that you need the right FTDI driver for your cable in windows.
regards,
Paul