OBD0 (with 10 MHz MCU clock)
Mode: Serial communication UART mode, 187500 baud, 9 bit no parity, 1 stop
Protocol: send the byte you want to receive wait for response
Send 9 bit data to ECM.
9th bit = 0 - the first 8 bit will address the Internal RAM (0-255)
(send [START]xxxxxxxx0[STOP] to address IRAM)
9th bit = 1 - the first 8 bit will address the External RAM (0-255)
(send [START]xxxxxxxx1[STOP] to address ERAM)
ECM transmits the content of i/e RAM address
OBD1 (with 10MHz MCU clock)
Mode: Serial Communication Multiprocessor Mode, 62500 baud, 8 bit, odd parity, 1 stop
Protocol: send the byte (in different modes) you want to receive wait for response
Send byte in data transmit mode, odd parity - the first 8 bit will address the Internal RAM 0000h-00ffh
(send [START]xxxxxxxx0o[STOP])
Send byte in address transmit mode, odd parity - the first 8 bit will address the Internal RAM 0100h-01ffh
(send [START]xxxxxxxx1o[STOP])
Send byte in data transmit mode, even parity - the first 8 bit will address the Internal RAM 0200h-02ffh
(send [START]xxxxxxxx0e[STOP])
Send byte in address transmit mode, even parity - the first 8 bit will address the Internal RAM 0300h-03ffh
(send [START]xxxxxxxx1e[STOP])
Send 00 byte in data transmit mode, odd parity - If the previous address was even, the ECU sends back the high byte of the word at the previous address
(send [START]0000000001[STOP])
OBD2 (3 pin DLC) Currently there's no information :(
OTHER COMPUTERS Currently there's no information :(
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