Direwolf PTT problem with tr(u)SDX

I’m trying to key PTT in direwolf on a tr(u)SDX transceiver using RTS through the com port assigned to the Digirig. But it isn’t working.

When I run command “arecord -l” on the Pi, I get:

**** List of CAPTURE Hardware Devices ****
card 0: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0

So I know the Digirig is assigned to port 0 and so I insert these lines into the direwolf.conf file:

PTT /dev/ttyUSB0 RTS

ADEVICE plughw:0,0

But this isn’t working. Radio isn’t keying PTT when I tell Direwolf to send a packet. What am I doing wrong?

That sounds frustrating. What does lsusb, or some equivalent on your OS, show?

73 Constrainted

Do you mean something like this?

pi@digipi:~ $ ls -l /dev/ttyUSB*

crw-rw---- 1 root dialout 188, 0 Feb 27 14:15 /dev/ttyUSB0

crw-rw---- 1 root dialout 188, 1 Feb 27 14:15 /dev/ttyUSB1

Yes, there are two USB ports mapped. One (USB0) is the Digirig. The other (USB1) is the USB port on the tr(u)SDX, which is used for CAT control.

I have the correct port. I know this because of the output from the arecord -l command that I showed in my original post.

That is not the issue. The problem is that RTS for PTT is not working.

That is the ls command. I hope the Raspberry Pi OS has something like this:

lsusb(8): USB devices - Linux man page (die.net)

73 Constrainted

Yes. This is what I get:

pi@digipi:~ $ lsusb
Bus 001 Device 008: ID 10c4:ea60 Silicon Labs CP210x UART Bridge
Bus 001 Device 006: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller
Bus 001 Device 004: ID 0424:2412 Microchip Technology, Inc. (formerly SMSC) Hub
Bus 001 Device 005: ID 1a86:7523 QinHeng Electronics CH340 serial converter
Bus 001 Device 007: ID 0424:7800 Microchip Technology, Inc. (formerly SMSC)
Bus 001 Device 003: ID 0424:2514 Microchip Technology, Inc. (formerly SMSC) USB 2.0 Hub
Bus 001 Device 002: ID 0424:2514 Microchip Technology, Inc. (formerly SMSC) USB 2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

OK great, but I thought the command would show you the tty unambiguously. Maybe commands “ls /dev/ttyUSB*”, then unplug the Digirig and do “ls /dev/ttyUSB*” again to see which device was removed. Then use that device with certainty that it is the correct ttyUSB for the Digirig. Or you may figure something out now that you are exploring more commands.

73 Constrainted

OK, looks like this is the solution:

ls -l /dev/serial/by-id


lrwxrwxrwx 1 root root 13 Feb 27 14:15 usb-1a86_USB_Serial-if00-port0 → …/…/ttyUSB0
lrwxrwxrwx 1 root root 13 Feb 27 14:15 usb-Silicon_Labs_CP2102N_USB_to_UART_Bridge_Controller_f04011914ea4ec11b69ae689a29c855c-if00-port0 → …/…/ttyUSB1

So it looks like I’ve got one mapped to ttyUSB0 and another mapped to ttyUSB1

I changed the PTT command to:

PTT /dev/ttyUSB1 RTS

And now it seems to work.

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73 Constrainted