Busy day yesterday. Missing REPL on EV3

[BertLindeman]

So many changes committed yesterday, that I do not know to which PR to add this.
Read them all, but only understand 0.5% of it.

Flashed ev3-firmware-build-4114-gitdfec425b.zip and connected USB <-> port-S1 as usual.

I see the EV3 boot:

EV3 initialization passed!
Booting EV3 EEprom Boot Loader

        EEprom Version:   0.60
        EV3 Flashtype:    N25Q128A13B

EV3 Booting system

Jumping to entry point at: 0xC1080000


U-Boot 2025.07-rc5-pybricks-2.0.1+ (Jul 06 2025 - 18:42:58 +0000)

DRAM:  64 MiB
Core:  10 devices, 10 uclasses, devicetree: separate
MMC:   da830-mmc: 0
Loading Environment from nowhere... OK
In:    serial@10c000
Out:   serial@10c000
Err:   serial@10c000
Autoboot in 0 seconds - press 'l' to stop...
Card did not respond to voltage select! : -110
SF: Detected n25q128a13 with page size 256 Bytes, erase size 4 KiB, total 16 MiB
device 0 offset 0x50000, size 0x100000
SF: 1048576 bytes @ 0x50000 Read: OK

But no longer an active REPL.
The program runs, but nothing on the serial port.

A small hint might help 😄

[dlech]

This was intentional. The stdio is no longer connected to the serial debug port. The change was made in pybricks/pybricks-micropython@e6ead10.

[ArcaneNibble]

I'm doing my current testing using this script (which runs on your PC)

import sys
import termios
import threading
import tty
import usb.core

dev = usb.core.find(idVendor=0x0694, idProduct=0x0005)
dev.set_configuration()
dev.write(1, b"\x01\x01")


def rxthread():
    while True:
        rx = dev.read(0x81, 512, -1)
        if len(rx) >= 2:
            if rx[0] == 2 and rx[1] == 1:
                rx = bytes(rx[2:])
                sys.stdout.buffer.write(rx)
                sys.stdout.buffer.flush()


def txthread():
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    try:
        tty.setraw(sys.stdin.fileno())
        while True:
            tx = sys.stdin.buffer.read(1)
            dev.write(1, b"\x02\x06" + tx)
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)


rxt = threading.Thread(target=rxthread)
rxt.start()

txt = threading.Thread(target=txthread)
txt.start()

This should probably be added into pybricksdev somehow...

[BertLindeman]

Thanks, will be happy to give it a go tomorrow (my time) Got libusb working on win11 and linux.

[laurensvalk]

The latest pybricksdev supports running programs on the hub via USB, so you don't really need the REPL per se. There hasn't been a release yet though.

[BertLindeman]

Yesterday did a pip install of github/pybricks/pybricksdev master repo, that did not work with yesterdays ev3 firmware.
Now flashed ev3-firmware-build-4120-gitaf9c1f4a.zip and pybricksdev run usb file.py does run and show the result.
After that it seems that pybricksdev hangs, which is not neat, but not important at this point in time.
Now to find out how to start the REPL via this route 😁