| Problem | Likely Cause | Solution | |---------|--------------|----------| | | Driver signature enforcement | Restart → Disable driver signature enforcement (Shift + Restart → Troubleshoot → Startup Settings → Disable driver signature enforcement) | | Device still shows as “Unknown” after install | Wrong chipset | Verify CH341 marking on PCB. Try Zadig (libusb-win32) if CH341 driver fails. | | COM port appears but programming fails | Incorrect software config | Ensure baud rate is not used – CH341 in SPI mode doesn’t need baud. Use SPI programmer software, not serial terminal. | | Device disconnects under load | USB power insufficient | Use powered USB hub. | | Linux: permission denied on /dev/ttyUSB0 | udev rule not applied | Add user to dialout group: sudo usermod -a -G dialout $USER (then logout/login) |
Ensure the physical slide switch on the hardware unit is set to the correct operating mode. It must be set away from the bootloader mode pin header to communicate properly with J-Runner for NAND operations. If you run into any issues during the setup, tell me:
Proper preparation will save you a lot of headache later. Before you plug anything in, make sure you have everything ready: drivers jr programmer v2 install
Upon reboot, a list of startup options will appear. Press the key or the F7 key on your keyboard to select Disable driver signature enforcement .
: A USB Mini-B cable (A-Male to Mini-B) is required for PC connectivity. | Problem | Likely Cause | Solution |
Once Windows boots with enforcement disabled, you can force the installation.
Which (e.g., J-Runner with Extras) are you planning to use with the programmer? Use SPI programmer software, not serial terminal
The currently showing on your JR Programmer hardware. Share public link
Right-click it and select > Browse my computer for drivers .