finally got things to work and i wonder why no-one made tutorial/how to.
1. Get Usbasp, boards assembled, mega2560 for serial read, KhazamaAVRProgrammer, Arduino Ide, Avrdude and Usbasp driver (zadig-2.5 app and there will be winusb v6.1.xxxx driver).
2. Via khazamaAVRProgrammer load eeprom to buffer and select firmware.hex file (or any other 32kb/36kb .hex file), choose atmega328p avr, and in program options set isp clk speed to Auto. Finally click on autoprogram. After that and few errors you will see green led working on pcb.
3. Via avrdude set fusebits. command is "avrdude -c usbasp -p m328p -B5 -U lfuse:w:0xff:m -U hfuse:w:0xda:m -U efuse:w:0xfd:m" w/o "" for usbasp programmer. Now you should see green led blinking rapidly.
4. Connect txd from bl49sp to serial1 rxd on mega, and bl49 rxd to txd1 on mega (should be pins 18 and 19). In ArduinoIDE make blank sketch and paste there
ABBC3_SPOILER_SHOW
void setup() {
Serial.begin(115200);
Serial1.begin(115200);
}
void loop() {
if (Serial1.available())
Serial.write(Serial1.read());
if (Serial.available())
Serial1.write(Serial.read());
}
Burn it to mega2560 (or other arduino) and use build in Serial monitor to see output from bl49sp on serial bus.
For few month my only problem was burning hex file (or .ino files in folder) to 328p, and i still think its not possible via Arduino IDE for guy like me
I had also that khazama programmer, but i didnt know all i had to do is set CLK speed to auto (as it would spit an error message anyway). Once i figured that out and seen only questionmarks in serial monitor i knew i have to burn those fuse bits. Its possible only with usbasp and avrdude as far as i know (and easiest).
PS:I didnt had time to connect o2 sensor, also it would be cool if there was fw for lsu4.2
PS2:
Back pressure compensation could be a thing with this wideband, as its open source and cheap enough to run on individual cylinders.