mcu reading and writing .

[petehall347]

please tell me what i need to read one of these in the photo and write to a new one ? i would of course prefer to be reading one still on the board .

[redwire]

Re: mcu reading and writing .

It seems to be an obsolete Renesas RL78-core MCU R5F10268 8KB FLASH. It looks like a chinese make of the IC by Shenzhen Zhouhengli Technology Co.

I see 5V serial-data pad on the PCB which would be used for programming/debug. You'd have to read the MCU programming datasheet to see if reading out the program is possible at all, there can be a code protect bit set to prevent this.
And we have no idea if the original bootloader is still there, it can be over-ridden to free up more memory.

[eccerr0r]

Re: mcu reading and writing .

speaking of microcontrollers... nowadays...

1 - how many of them do not have read / write protect fuse bits?
and
2 - how many manufacturers leave them unprogrammed and allow reading?

[petehall347]

Re: mcu reading and writing .

its in a greenworks 82v battery pack .i have access to working ones ,,this one decided to short at 1.6 ohms between vss and vdd .. think it was maybe ok before i soldered a wire back to a cell in the pack that was broken .
charger reported faulty pack . a jump start normally works but someone had been inside before me .

[petehall347]

Re: mcu reading and writing .

is there any chance it will write itself like car ecu.s can ? i know it talks to the charger if that means anything. i am having to learn about these things to feed myself .
thinking about it though i guess the charger just switches it on ..

[eccerr0r]

Re: mcu reading and writing .

doubt it... it would probably need to expose more contacts to the charger to write when there may not be a need to....

Hate it when I work on something that someone else had worked on before...mostly if they made it worse...

[petehall347]

Re: mcu reading and writing .

what is the best lower price tool i need to at least try and read a good one of these chips and write to a new one ?

[stj]

Re: mcu reading and writing .

specialist shit like that, your best bet is scouring the net for a homebrew solution like an arduino
otherwise only manufacturer tools or very expensive universal programmers are likely to handle it.

start with a datasheet.

[petehall347]

Re: mcu reading and writing .

been looking at the datasheet and cant see anything about read protect . but i did skip through it . https://cdn.badcaps-static.com/pdfs/...d62d2399f6.pdf
having something that will at least be capable to read it is needed the most .

[SMDFlea]

Re: mcu reading and writing .

been looking at the datasheet and cant see anything about read protect . but i did skip through it . https://cdn.badcaps-static.com/pdfs/...d62d2399f6.pdf
having something that will at least be capable to read it is needed the most .

See chapter 24 of the RL78/G12 User's Manual -

[petehall347]

Re: mcu reading and writing .

the suggested interface is a bit expensive at £750, maybe the chinese have a copy one . or does it really need a remesas one ?

[stj]

Re: mcu reading and writing .

page695 implies you cant read it out - only write to it.

[petehall347]

Re: mcu reading and writing .

from what i read last night it appears it can be read if not being written to at the same time . its uses uart by the looks of it .also there appears to be a debug and admin mode maybe i should email renesas to ask them to clarify things .
suppose i could throw the battery pack into the spares box and forget it for now . i guess i will be seeing more and more of these things to repair .

[stj]

Re: mcu reading and writing .

programming

[petehall347]

Re: mcu reading and writing .

maybe i should be researching open source programs that will work with this bms pcb .

[eccerr0r]

Re: mcu reading and writing .

From what I take from the datasheet, if the code on the chip does not provide a read API, then you can't read it directly. You can indirectly read it however, but it's the equivalent of hacking passwords bruteforce and this probably would take years to complete...

[petehall347]

Re: mcu reading and writing .

not sure if these can help me but looks interesting . https://foxbms.org/

[eccerr0r]

Re: mcu reading and writing .

You can always make your own BMS but it needs to match the API of the existing chip...

[petehall347]

Re: mcu reading and writing .

reverse engineering is what's needed as far as i can see .. its fairly easy to work out what's expected from the program but my limited knowledge with programming is holding me back ..i could learn how to do it but i don't want to tax my brain doing so . this battery charging and monitoring must be pretty much the same for all similar battery packs .

[clearchris]

Re: mcu reading and writing .

speaking of microcontrollers... nowadays...

1 - how many of them do not have read / write protect fuse bits?
and
2 - how many manufacturers leave them unprogrammed and allow reading?

You can read out a bootloader in many cases, but often not the main code. You upload the new program, the program reads the bootloader and copies it to a section of memory that you can read or dumps via serial port.