Today I opened the lid under my Monoprice Minidelta printer that I bought on Amazon end of last year (11-2021).
Unlike what I found on the net, I appear to have an upgraded motherboard that is joined with the TFT.
Both the MB and TFT have their own pocessor and -TFT update files, available from the Monoprice website and to be found on http://mpminideltav2.com/doku.php?id=octoprint:config.
The GD32F103 ARM processor is the 32-bits direct STM replacement and is a very capable processor. The board also looks very good, so I won’t be replacing any of it.
I am however trying to build my own firmware for the MB, based on Marlin and the STM32 lookalike. BUT- the LCD and the pin connections for the hardware ia all unknown to me, so it might take some more investigations..
For the short term, I will install a Pi Zero2 and adjecent PI IR camera in the printer, along with a top LED light. The original new printer’s firmware allows the use of Octoprint so I can add this printer easily to my managed stock of remotely managed 3d printers. Without modding the original firmware.
In the bottom of the printer, enough space is available to mount the RPI and I will switch the LED with the PI’s GPIO managed switches, and a MOSFET board. Preferably with a PWM driver, or just on/off if this works better.
Another required upgrade will be to get a PEI sheet on the hotbed and replace the plasticy extruder with a dual drive one..
