[UPDATED] MTCD - Verified Cross compatible MCUs | Game 4ndroid

[How to MTCD - Verified Cross compatible MCUs](McuUnmatchUnlock.apk) MCUs found to be cross-compatible between MTCD units, which includes PX3 and PX5 variants, which share identical mainboard hardware and MCU Chip STM32F091.

The following MTCD & MTCE (as of v2.56) MCUs have been validated as cross compatible on 1024x600 units:
- MLT - 01/07/17 - caution - has resulted in issues for some @leonkernan
- JY
- KBT - 08/12/2017 - thanks @abagos
- KD (v2.40_2 - enables bluetooth hands free in both front speakers)
- KGL
- KSP thanks @Overmann
- GS - Note "version unmatch" error and fix below No issue experienced on MTCE going from JY 2.80 to GS 2.78 and back to HA 2.80 - March 2018
[B]- GS compatible on MX (see post #513)
- HA (v2.56 06/07/17 - note v2.52 on enables "shutdown delay when acc off" menu) HA MTCE (30/09/17) V2.65 https://www.sendspace.com/pro/dl/ufie8k

I initially upgraded to KD 2.40, then HA v2.52 after first exporting the MCU settings.
Note that I had to reapply MCU settings in [factory sertings] to configure radio, LED, bluetooth, hardware keys, volume levels between radio, bluetooth, system etc.

MCUs were previously thought to be manufacturer specific - e.g. HA, JY, GS, KD, however I have found that they are compatible and of interest where there is either a specific issue with your MCU (e.g. bluetooth out of one speaker, to enable PX5 sleep mode control) or the vendor has long ceased to support & release updates - such as JY.

MCU cross-compatibility became of interest to me when I upgraded my JY [MCU v2.06_2] PX3 with a HCT PX5 SOM and wanted to enable the MCU specific menu item [shutdown delay when ACC off] to control sleep as found on HA/Dasaita

I then started comparing same version number firmware files from various manufacturer MCUs with a text compare tool. From this work, I had enough info to compare the latest HA v2.52 and conclude it 'should' be compatible. Indeed it is.

As always, check first (suggest confirming MTCD, MCU Chip part number, view/compare the fw files, ensure you have original MCU FW, backup MCU settings or document the settings to ensure your hardware controls, volume control, bluetooth, radio, canbus etc are setup correctly). Apply at your own risk.

For all those with a GS: Our unit is compatible with the MTCE MCU but you have to restore your settings and maybe to manually reconfigure your touchscreen and buttons. There is a simple function to do this in the factory settings (126) which is called key study. My touchscreen was also swapped by the x axis. I had to go with the swapped touchscreen into the settings, configure it, reboot the unit and everything was fine. For the buttons you have also the possibility to use short press and long press buttons, which is great because our units (at least mine) has only five buttons and no return button. So I use now the power off button as return in short press mode and power off in long press.