[Ruibarbazul]

Hi everyone.

To change my CNC from parallel interface to USB interface I bought the BSMCE04U module.
But with difficulties in understanding how to connect this module, I decided to draw its schematic.

Below is a copy of the schematic for those who want to visualize how this module is internally
to better understand its functioning.

Some capacitors could not identify the capacitance.

Please, if you find errors, please let me know.

RV mineirin

[berin]

This project I have set aside for some time, I'm working on other projects that are more important currently. Ruibarbazul I see some differences in the pin assignments. I believe you are correct and what I posted is in error thanks. I have X one of the X pins going to PA not PB, which would make code very hard. hum that changes things. I dont have time to work on this project currently, maybe someone is working on STM32 GRBL and could help with coding for this board.

[SileliS]

Hello,

I will port GBRL STM32 code ( https://github.com/whoim2/stm32-bluepill-grbl-pcb ) to the bsmce04u-pp but first of all I want to maintain present firmware. There fore I have quiestion If anybody have downloaded firmware from STM32? I assume that there is protection bit but based on variety of bsmce04u-pp clones maybe not.

@Ruibarbazul Can You post sch file instead of jpg?

[SileliS]

1) I have some idea how to make this board works both as Mach3 and GBRL controller. STM32 have NRST pin so it is possible to halt originally soldered mcu and on the top of it connect (some kind of sandwich “chip-on-chip” simple PCB with programmed STM32F103 - GBRL firmware + chip selector).

The firmware is easiest thing but I have to figure out how to connect this second mcu. I have idea to design sandwich socket like in old Amigas but there is no sold thing and have to design own (unless I am better software developer than mechanical). :/

2) Other solution is to design own board with both mcu and resolder oryginal form bsmce04u-pp
@Ruibarbazul Can You share Your chematic as sch file?

[xuraax]

1)

The firmware is easiest thing but I have to figure out how to connect this second mcu. I have idea to design sandwich socket like in old Amigas but there is no sold thing and have to design own (unless I am better software developer than mechanical). :/

Whilst browsing this site I stumbled upon this most interesting thread. I was wondering whether this idea has been developed since last year's contribution.

The last contribution proposed installing a second mcu on top of the existing in order to carry out the development?

With the price of these boards at a mere $5 or so, wouldn't it make more sense to simply buy a second board and overwrite the existing software. If this cannot be done because the chip is write protected it seems easier to replace the STM32 with a new one instead of installing one on top.