DSO 150+STM32Duino+black magic = lot of fun

I have bought a second DSO 150, a cheap STM32 based oscilloscope.
They are low frequency, single channel, but cheap and easy to modify.

Mine is now battery powered, with a usb plug to charge it
(the stuff is 3D printed, model is available on thingiverse )



It appears that they are pretty close hardware-wise to our beloved bluepill.

Solder the SWD pins, connect our custom blackmagic and we are ready to go.



First step, flash a random bluepill bootloader so the board boots as a bluepill. Works.
Second step: the screen. Looking at the Open DSO 150 project gives a lot of information regarding the hardware setup.
The screen pinout is a bit unusual :
   Read PA6
   Write PC15
   RS         PC14
   CS         PC13
   Reset PB9

Data is sent using the 8 lower bits of Port B.

So first step is to patch the 8 bits ILI9341 lib  to use the right pins.
.... and it still does not work

After digging a bit and probing the pins, conveniently placed on a test header, PB3 and PB4 do not work.
Stm32duino forum to the rescue : They are also jtag pins.

A quick call to
     afio_cfg_debug_ports( AFIO_DEBUG_SW_ONLY);
To disable jtag pins, and it works now, filling the screen with random colors

First step completed, i can boot the board and work a bit with the screen

The thing is, it is not a ILI9341 320x240
It is a ST7789 240x320, mostly compatible but rotated 90°

To be continued

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