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CFA-632-YDI-KS problem constantly rebooting and then turning off


New member
I got a CFA-632-YDI-KS with firmware version 3.4 just yesterday. It came with the jumper for USB power closed, so I removed that, since that's what the datasheet said to do for 232 operation. I tried the RS-232 full swing from my computer, which had a USB to serial converter. I wasn't getting the expected voltages for powering the CFA, so I just used a 12v battery jacked into the DB9 plug, whose ground was shared with the ground of the USB to serial device. IT seemed like an innocent way to get 9-15v. Well I was able to send a letter ('A") through cfTest.exe to the CFA, but then it also added a couple extra symbols, and then would reboot about 1 times every 0.75 seconds (several times), and then the screen would go blank, but the back light would still be on. So, I gave up on the 232, and made sure JP2 was shorted, and then shorted JPDFLT, found a printer USB cable, whose wires were red, black, and twisted pair green and white. I saw that your USB cable wires in the datasheet were the same colors, so I used them in the same order you suggested. I successfully changed the mode to USB (But only by powering it with J2. Only using the 4 wire USB connection would not turn it on)

So, I attached the 4 USB wires to the USB connector on the board (top to bottom, red, white, green, black). I plugged in the USB to the computer, and nothing happened on the CFA. The only way I can get +5v power to turn it on is to connect the +5v to J2. But cfTest.exe doesn't recognize that anything is plugged in when I have the 4 wires connected to USB, the CFA is in USB mode, and the +5v/ground are connected from the USB to JP2. I wouldn't have thought that you would need to connect anything to J2. Any suggestions?
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