Flashing OpenBK on CB2S with BK7231Flasher and Itchiptool - Connection Issues

Hi,

I bought 2 of these controllers: https://es.aliexpress.com/item/1005005872942237.html

They had a CB2S inside, I desoldered it:




I soldered some dupont cables:





And I'm using both of these programmers:




But... it's impossible to flash OpenBK.... (BK7231Flasher 1.1.6 used.)



Tried Itchiptool 4.10.1, and the only success is when I short the CEN pin with Ground, the Connecting to the ship (in yellow at the photo), changes to software reset / hardware reset.



But nothing at all, no connection...
Any idea? I just can see that there is NO RX1, it's only RX2, and it doesn't seem like a typo...


Edit: more info: Tx light is blinking like if the program is sending data but the RX light is always off, only lights minimal when I short CEN to ground.

You are connecting your wires incorrectly.
I had this module.
It has misleading silkscreen. The 3.3V and GND are not where you think they are.
Please double check with your PCB.
I think the real 3.3V and GND pads are as shown here:

Your module has mixed pad markings and they are misleading. Again, please double check, but I already had module looking exactly like yours and I flashed it the way like I would flash old CB2S...

Added after 1 [minutes]:

PS: To be honest, when you look at the pin marked as "P24", you can see it's really a ground pour plane:

So I think my idea checks out.

Please connect it correctly and flash with our tool: https://github.com/openshwprojects/BK7231GUIFlashTool

Oh my god...

I was so tempted yesterday to do this...

Thanks a lot, it's working on the first try!

I am glad to hear your issue is resolved. I had exactly the same module as you, and I checked it well against the traces on the main PCB. The silkscreen is wrong, just as I said.

You're lucky that you haven't damaged the module, but luckily they have protection diodes at all GPIOs, something like this (without resistor):


If you need futher help with configuring OBK, please open a new topic