Serial comms over USB

Hi Guys,
Bit stuck with this one…
I’ve got a USB device that can communicate through the USB using a simple comms package and it works fine in Raspbian on the Pi.
Is it possible to write a BASIC program in Risc OS that would allow me to do the same thing? Am I right in thinking OS_SerialOp and OS_Byte 7 and 8 don’t apply on a Raspberry Pi?
The comms settings are 115200 8-N-1.
I’ve noticed a few new modules in RiscOs 5 that are for the serial port but don’t know what SWI’s they provide and if this would allow me to communicate with a device over USB.
Can anyone give me a snipped of basic code I could follow or just let me down gently and tell me it’s not possible!
Many thanks

First question does it have a driver so it reports as an serial port under RISC-OS ?. Check with Filer_OpenDir devices:$ does it show ? No first that working OS_Byte will certainly not work because that only works with the first serial port. If it show best is to treat it as a file.
Somewhere is a thread about an driver for an USB serial but as with MS-Windows USB serial dongle can be a pain in the ass.

Thanks,
Well that’s hopeful! I get Serial 1, USB1, USB2 and USB3 when it’s not connected, and USB4 turns up when it is.
Not sure where to go from here. I can’t double click the file as it’s a device. Do I treat it like a file and read and write using BPUT and BGET?

Go to the command line and do *USBDevices

You should see the device identified as something like Prolific Technology Inc. USB-Serial Controller (that’s mine).

If this is the case, then try SerialUSB available from http://ftpc.iconbar.com/usb/index.html
It will work with CP210x devices, the oft-cloned PL2303, the CH340, CDC and FTDI devices. In short, if there’s a USB serial interface that isn’t something weird like MIDI, this driver is your first port of call.

There’s an example in using it, but, yes, essentially you:

• Open files (input and output) using a special string to set up the word format and baud rate (that means the file path will look something like SerialUSB#baud=2400;data=8;stop=1;noparity;nohandshake;noblock:".
• Use OS_Args 9 (IOCTL) if you need to use/read the control lines.
• Use BGET and BPUT to read and write, remembering that the input and output are two different file handles. ;-)

There’s an example provided. It’s in C, but it’s pretty clearly written so ought to be enough to get you started if you’re using BASIC.

I wonder what the USB serial device is?

Thanks again!
So *USBDevices reports as STMicroelectronics ChibiOS/RT Virtual COM Port
That sounds promising…
*SerialUSBDevices reports as a CDC device, wherever that is, with vendor number 0483 so something’s being read.
I tried SerialUSB but sadly nothing. It looks to have the right setting at default and I’ve tried -echo and -cflf options
I think I need to have more of a fiddle…
This is for a TinySA spectrum analyzer. You can control it via commands and once I crack this I can write a semi-automated measuring rig for EMC emissions. Probably not a lot of use to anyone else though… ;o)

Hi,
I don’t know what you want to do but you can test the connection with hearsay.
also available from http://ftpc.iconbar.com/usb/index.html (Colin Granville)
I tested with an Arduino and an ESP32 module.

For the TinySa, it must be able to work in console mode with hearsay?

Woohoo! We’re making progress… sort of!
Although it looks like nothing is being sent back I can tell it’s receiving commands correctly as I can change the settings on the TinySA.
Any commands that return some text don’t appear to do anything though.
Thanks for the tip on Hearsay, I’ll give that a try tomorrow.