EM Firmware Flasher

This standalone software lets you flash firmware onto your V2.0 adapter. You will need this to update your adapter firmware. It is basically just a wrapper for "stm32flash 0.4" to make the process as simple as possible.

Click here for step-by-step instructions on reflashing your adapter firmware.

Download Links:
EM Firmware Flasher V1.0

EM Firmware Flasher V1.0 Screenshot


Please ensure that you choose the correct adapter type and version before downloading!

Adjust the GC and CC mapping sensitivity below:

More SensitiveLess Sensitive

Stick Mapping Plot

Select Adapter Type:

Select Firmware Version:

Firmware Version Changelog

  • Input display works with the official 4-port GC->USB (Wii U) adapter (and other high poll-rate devices of ~1ms)
  • Minimum controller poll delay reduced to 1ms (from 1.5ms)
  • Input display works with the Mayflash 4-port GC->USB (Wii U/PC) adapter (and other higher poll-rate devices of ~5ms)
  • Bounds-checking is applied to calibrated controller joystick values (so they no longer wrap)
  • The OLED display turns off after a timeout period (default is 10 seconds, but adjustable between 3-30 seconds)
  • Master Quest button mapping fixed (N64 only)
  • F-Zero and Majora's Mask button mapping fix (they were swapped) (N64 only)
  • Ocarina of Time GZ mapping removed for versions with no N64 input (as identical to Ocarina of Time mapping) (GC+CC only)
  • Console response high/low timing adjustments
  • Initial firmware release