[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.

[elmerfud]

There is a nice firmware on github which upgrades this board from mach3 to ugs, you just need the 4 wire usb programming tool from ebay, maybe $5usd.

[berin]

xuraax xuraax. Hello sorry I have been more or less MIA from everything for a long time. My father battled stage 4 cancer for 5 years. I got caught up being the """"only"""" one of his many children to aid and take care of him. Problem is that he became a very angry person with bitter bitter BITTER BITTER denial of his failing health. Do to his many ill with intent choices. Produced very harsh financial issues for me. I've more or less lost almost $ almost everything. And its not over by a long shot as of the posting date of this post.
As to the board. I was able to access the board, but I was not able to recover a copy of the original virgin firmware for mach3. On the other hand I was able to clear and program the stm32 with simple hello world test code. I am NOT much of a programmer. I'm a designer and hardware person. others will have to design and compile the code. I would love to see these boards with marlin or stm32-grbl LOADED. you may find this photo link of mine of interest. https://photos.app.goo.gl/ZVxFnvZABBCnJGsW9 Also I wish someone would produce and publish GRBL for the new arduino uno r4. It would be a drop in massive upgrade for my laser etcher.

[berin]

elmerfud got a link to the mach3 to usg github your talking about? I'd love to look at it.