Just a question. How do you parse the hex file and send it over to the arduino? Llaaaatt[dd.]cc If this is the format of a hex file, for every line you get the 'aaaa', and then assigns it to AH and AL in the sketch as i see.

Foton Tractor Service Manual more. But what about data? Do you get all the [dd.] and assigns every byte of it to data, and then send it to the 8051 Microcontroller? I mean, If dd is a byte of data, do you get each dd and send it over to arduino? And then, in the next line, do you do it all over again?

8051 Microcontroller is a programmable device which is used for controlling purpose. 8051 is programmed only once by 89C51 can be re-programmed.