Issues with our Reachy Luos system

We have been working on our independent Reachy build and have run into some problems with the Luos system.

First issue, after re-routing some power our head gate is completely unresponsive. It doesn’t show up in our pyluos-usb-gate discover command at all. I’ve ensured I am using the correct Luos USB micro port and several different USB cords. It was previously responsive and was driving the DXL board for the antennas just fine.

Second issue is we are adding the Left arm to our Reachy and we are trying to set up that from scratch. I uploaded the latest firmware to the new boards (what I thought was successfully receiving only this error but a successful file download msg:

luos-modules dano$ bash ./GateArm.bin

dfu-util 0.9

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to

dfu-util: Invalid DFU suffix signature
dfu-util: A valid DFU suffix will be required in a future dfu-util release!!!
Opening DFU capable USB device…
ID 0483:df11
Run-time device DFU version 011a
Claiming USB DFU Interface…
Setting Alternate Setting #0
Determining device status: state = dfuERROR, status = 10
dfuERROR, clearing status
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 2048
DfuSe interface name: "Internal Flash "
Downloading to address = 0x08000000, size = 88054
Download [=========================] 100% 88054 bytes
Download done.
File downloaded successfully
Transitioning to dfuMANIFEST state

The gate is discoverable using our pyluos-usb-gate discover command. However python hangs and never never returns a new >>>> prompt after the command:

from pyluos import Device
device = Device(’/dev/ttyUSB1’)

Thirdly, if I did make a loop in the robus network by mistake (I don’t think I did, but I am trying to rule it out) what would be a diagnostic step to uncover that? And does that mean I fried the gate?

Any troubleshooting advice would be greatly appreciated.

FYI here is the output when python freezes after I assign the device USB port and I Cntr-C:

Traceback (most recent call last):
File “”, line 1, in
File “/home/pi/venvs/reachy-env/lib/python3.7/site-packages/pyluos/”, line 96, in init
File “/home/pi/venvs/reachy-env/lib/python3.7/site-packages/pyluos/”, line 150, in _setup
state = self._poll_once()
File “/home/pi/venvs/reachy-env/lib/python3.7/site-packages/pyluos/”, line 206, in _poll_once
self._state =
File “/home/pi/venvs/reachy-env/lib/python3.7/site-packages/pyluos/io/”, line 18, in read
data = self.recv()
File “/home/pi/venvs/reachy-env/lib/python3.7/site-packages/pyluos/io/”, line 60, in recv
return self._msg.get()
File “/usr/lib/python3.7/”, line 170, in get
File “/usr/lib/python3.7/”, line 296, in wait

Hi @RoboCoLab ,

It sounds like an hardware problem regarding the head gate. Perhaps a ground reference problem. You should try to reach @Pierre from Pollen about it, they have a better understanding of the power circuit of Reachy.

About the left arm gate I thin Pollen Robotics use specific revision of Luos, Gate, and Pyluos for Reachy. They probably share some revisions somewhere.

If you want to use really native Luos revision you will have to use embedded IDE such as Platformio and compile it by yourself. Some boards from Pollen is not compatible with our examples and with latest revisions of Luos.

Looks like there was a bad firmware version i was downloading. That was fixed by getting the correct version. However it does look like we fried the gate and dxl board :frowning: i am pretty sure i looped the power.

Thanks for the reply though!