Hello, I have a Jupiter-T GPS timing module board that is connected to a home made board with a Microchip PIC 12F629 microcontroller. They form a simple amateur radio GPSDO unit(GPS disciplined Oscillator for my radio lab) They communicate eachother using serial TX and RX 5 volt signals. Recently it has problems to get the fix and want to debug it (antenna problem or module problem, who knows).
I have a NetBSD RaspberryPi4 board with a TTL/USB converter (TX, RX and GND pins, ftdio driver). I have connected only the RX and GND pins of the TTL/USB converter to the TX pin of the GPS module to see what information the GPS board is sending to the PIC board. I added rw permissions to device the wheel group so I can talk to the converter from the wheel group without root privileges netbsd-raspa4$ ls -lh /dev/ttyU0 crw-rw---- 1 uucp wheel 74, 0 Oct 14 11:25 /dev/ttyU0 "cu" command works just fine: cu -l /dev/ttyU0 -s 9600|hexdump -C|less netbsd-raspa4$ cu -l /dev/ttyU0 -s 9600|hexdump -C|less 00000000 43 6f 6e 6e 65 63 74 65 64 0d 0a 0a 40 40 45 61 |Connected...@@Ea| 00000010 0a 0e 07 e8 09 1b 0e 3b 9a c9 fe 0a ad d0 1e 02 |.......;........| 00000020 b7 82 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 00000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00000050 00 00 00 00 4a 2e 0d 0a 40 40 45 61 0a 0e 07 e8 |....J...@@Ea....| 00000060 09 1b 10 3b 9a c9 fe 0a ad d0 1e 02 b7 82 7f 00 |...;............| 00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000000a0 4a 30 0d 0a 40 40 45 61 0a 0e 07 e8 09 1b 12 3b |J0..@@Ea.......;| 000000b0 9a c9 fe 0a ad d0 1e 02 b7 82 7f 00 00 00 00 00 |................| 000000c0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000000e0 00 00 00 00 00 00 00 00 00 00 00 00 4a 32 0d 0a |............J2..| I get good Zdiac Binary protocol frames. I read somewhere that I could get same behaviour with this commands this way: netbsd-raspa4$ stty -f /dev/ttyU0 9600 netbsd-raspa4$ cat /dev/ttyU0 But I do get nothing from the cat command. Probably something stupid but I have been strugling with this with no solution. Thanks. Ramiro.
