On Fri, Apr 5, 2019 at 2:19 PM Thomas Morehouse <[email protected]> wrote:
> "Check your USB-Serial cable first. That's the USB cable with a DB-9 male > RS232 connector. Plugged to the PC. No cables connected to it. > > Type in TeraTerm. Question: Do you see any characters? If so, you have > echo on. If not, echo is off. Go into TeraTerm settings and turn echo on, > and try again until you see the characters you type." > > OK - only the usb/serial cable, plugged into usb port of laptop. No > characters appear. Change TeraTerm Terminal (VT100) to Echo. Characters > appear. > > Next step: > > "Short pin 2 to pin 3 on the DB-9. > > Type in TeraTerm. > > If you see only see one character per keypress, the adapter fails the > test. If you see 2 characters per test (one for the echo, and one > transiting the cable) then it passes the test." > > I shorted 2 and 3 on the DB9 end of the usb/serial cable, while cable is > still plugged into usb port. > > I typed one character. One character appeared on laptop screen. > > > Seems strange the 2 - 3 shunt on the 102 pins would fail loopback test > *and* the 2 - 3 shunt on the cable fails the test on the laptop also. > > Well we know why that is, because you were using the barcode port. Could you try a simple loopback again on the M100 to confirm no issue? I've seen very few failed M100 RS232C ports. Here's a picture of my silly loopback on the m100. Just a male DB25 connector plus a paper clip. Only because I don't want to risk damaging the M100 connector by shoving the wrong gauge wire into it. m100_loopback.jpg <https://drive.google.com/file/d/1B5CNzk_1-T8HTtxrDu9UJPd83t6l0CoO/view?usp=drive_web> -- John.
