WARNING !!!! This is not perfect and u can destroy ur chip! I dont take any responsabillity for ilegal use !!! (xnc)

m35080_Read_BitBang

"This default Skech now reads the full memory of EEPROM chips of the m35080 family like M35080, 08ODOWQ, M35080VP and 35080V6. The read begins, after any kind of serial data is transmitted to the arduino (e.g just press the space bar and hit enter)."

One wrong comment, still read ok just 1 byte, second byte was wrong. I added "full_read_write_VIN.ino" to correct that (xnc). Working on SPI branch, may set better the timing.

Secure Incremental Memory ranges from 0x00 till 0x1F
Standard Memory ranges from 0x20 till 0x3FF

Arduino

I used an arduino "nano"(xnc), but any arduino which supports SPI is fine. Just switch the board in the arduino IDE.

M35080 EEPROM

A datasheet is included in this repo. Connect Chipselect, Clock, In, Out, Vcc(5V) and Vss accordingly. Make sure, that max. current never exceeds 10mA.

Write to Memory (0x20 till 0x3FF)

You can write to memory using the write_8() function.
Please backup your full memory before you make any changes.

Example:

adr = 0x2F1;
char val = 0x20;
write_8(adr, val);

or also

int adr = 0x2F1;
intchar val = 0x00;
char content[] = {0x12};
for (int i = 0; i <= sizeof(content); i++) {
  write_8(adr, content[i]);
  adr = adr + 0x1;
}

Write to secure (incremental) memory (0x00 till 0x1F)

You can write to memory using the write_secure() function. Please keep in mind, that you can only count up these values, so be careful what you write. YOU CAN'T WRITE LOWER NUMBERS THAN WHAT IS ALREADY IN THERE

Example:

int adr = 0x00;
char val1 = 0x26;//xnc//
char val2 = 0x12;//xnc//was most wrong example, 
//first byte is just first byte - using previous version (reversed bytes)
//just destroyed forever my M35080, all incremental registers are now "0xFF" 
//so i need help to find out the ERASE command - nothing worked until now 
//despite i tested all commands from 0x08 to 0xFF, no one set the WIP bit on status register.
write_secure(adr, val1, val2);

Decoding BMW Cluster Information on E-Series Models

Secure memory info contains byte pairs. So every pair gets a hex index (which is NOT equal to the hex adress).
If our example memory looks like this:

00	01	02	03	04	05	06	07	Memory-Adress
26 13	26 13	26 13	26 13	26 12	26 12	26 12	26 12	0x00 - 0x0F

08	09	A	B	C	D	E	F	Memory-Adress
26 12	26 12	26 12	26 12	26 12	26 12	26 12	26 12	0x10 - 0x1F

The Hex-Value for the milage (km) is 26 12 5 (bec. its the 5. column where the hex changes from 2613 to 2612) which equals 155.940 km in decimal.

The VIN is placed at 0x2E8- 0x2EF where 0x2E8 - 0x2EE contain the last 7 digits of the vehicle VIN and 0x2EF probably contains the checksum (not sure about that). Since coding a new VIN from standard manufacturer tools is not possible, you may want to write the whole are blank (0xFF for 0x2E8- 0x2EF). After that, it's in factory state and the VIN can be set with manufacturer tools via OBD (but only once, so do this right after installing the cluster)

Example VIN:

| Memory-Adress| 0x2E8 | 0x2E9 | 0x2EA | 0x2EB | 0x2EC | 0x2ED | 0x2EE | | :--:|:--:| :--:|:--:|:--:|:--:|:--:|:--:|:--:| | Hex | 4B | 54 | 31 | 37 | 37 | 32 | 37 | 35 | | ASCII | K | T | 1 | 7 | 7 | 2 | 7 | 5 |

So here the last 7 Digits of the Vin are KT17727. For fitting a used cluster you want the whole are to be 0xFF.