Hi,
I recently bought E750 Mudi device. Unfortunately while playing with CLI (ssh access) I run mcu_update program with /etc/config/mcu parameter 
Now my LCD displays only “MCU Update” message. What can I do? Anybody has original firmware for this MCU? I would like to reflash it with proper firmware.
Thanks
Michal
Ok. Another question: is it possible to refresh firmware that was flashed wrongly. Currently:
ubus call service delete ‘{“name”:“e750_mcu”}’
mcu_update e750-mcu-V1.0.7-56a1cad7f0eb8318ebe3c3c46a4cf3ff.bin
and waiting… (almost 20 minutes)
You can find the tutorial to flash the clean firmware here:
Thanks for the hint but as far as I understand this procedure works when openwrt/gl.inet firmware is broken. My problem is a little bit different as I broke MCU firmware And it means that device doesn’t respond when I press power on / shutdown button.
Does the E750 boot automatically when plugged in? If so, that’s a way you could try to do it, hold the reset button and then plug the device in.
Ok. I flashed firmware using U-boot procedure but it didn’t help. I’ve factory firmware but display is still inactive.
Hmm then I am at a loss 
You should try contacting the support by email: support@gl-inet.com
They are able to sent you specific firmware for specific issues. They once saved me after I messed up flashing OpenWRT😄
There is a second reset button. There is a MCU reset pin near it on PCB. Anyone knows something about it?
I never knew about that😄
Thus I’m afraid im no further help here, but maybe @alzhao could take a look?
The reset the mcu.
When pressed, the router just reboot.
This fixes if the screen just died or the router is not be abled to turn on/off.
Hi @alzhao
So the question is: is it possible to repair (reflash) the MCU that I broke with command:
mcu_update /etc/config/mcu
It seems that mcu_update doesn’t check input file and just tries to push it to MCU. I found 1.0.7 firmware on this forum but I think software connection to MCU is lost because of above command. Is there any way to upload proper firmware or should I live with blank LED screen?
Kind regards,
Michal
If you rebooted already, then the MCU cannot be debrick from the openwrt directly. Have to reflash the chipset.
Any hint/description for MCU pinout? I’ve some programming/flashing interfaces in my drawer 
Probably I can try to do it…
Thanks for support.
Michał
https://www.nuvoton.com.cn/tool-and-software/software-tool/programmer-tool/
Here is the official burning software
There are 5 solder joints on the board
Thanks for this information, I was able to fix my unit using the .bin firmware with a nulink programmer clone (bulink) and software from the link above. Though I don’t know why the mcu firmware upgrade failed with the mcu_update command… (I have more success upgrading MCU firmware with the latest beta).
