I really need to disable RP2040 reset via baud rate in Arduino IDE (touch1200)

[ea4eoz]

Hello.

I'm implementing an ancient USB peripheral / protocol into a RP2040 using the Arduino IDE and I'm facing a lot of problems with the enabled PICO_STDIO_USB_ENABLE_RESET_VIA_BAUD_RATE feature from the Pico SDK.

Unfortunately the (legacy) control program running in the PC opens the serial COM at 1200 bauds, so the RP2040 resets itself and enters into mass storage programming mode. I have also noticed while windows reboots, something is polling the serial ports also at 1200 bauds, so once the PC boots, the RP2040 is in programming mode.

After a lot of trial and error I noticed the Arduino IDE uses a precompiled libpico.a library and it never recompiles it no matter what I do.

I tried to recompile the Pico SDK with PICO_STDIO_USB_ENABLE_RESET_VIA_BAUD_RATE disabled in the stdio_usb.h source file, but the compiler script (make_libpico.sh) never touch that file.

I tried to add a platform.local.txt file but it gets ignored.

I'm running out of ideas, so... what is the right way to disable any reset feature via USB using the Arduino IDE? Programming pushing the boot button is ok for me.

Thanks in advance.

[earlephilhower]

Check (and comment) out:

arduino-pico/cores/rp2040/SerialUSB.cpp

Lines 182 to 198 in 5e2fbf3

	static void CheckSerialReset() {
	if (!_rebooting && (_bps == 1200) && (!_dtr)) {
	if (__isFreeRTOS) {
	__freertos_idle_other_core();
	}
	_rebooting = true;
	// Disable NVIC IRQ, so that we don't get bothered anymore
	irq_set_enabled(USBCTRL_IRQ, false);
	// Reset the whole USB hardware block
	reset_block(RESETS_RESET_USBCTRL_BITS);
	unreset_block(RESETS_RESET_USBCTRL_BITS);
	// Delay a bit, so the PC can figure out that we have disconnected.
	busy_wait_ms(3);
	reset_usb_boot(0, 0);
	while (1); // WDT will fire here
	}
	}

[ea4eoz]

Yes yes yes!

It worked like a charm.

Thank you!