I want to write 2 C51 programs, and they don't not run simulanesouly. One of the hex will reside at CODE area, the other will locate at XDATA area. Because the two hex file have some common functions. I want to save XDATA area space, how could I link some functions in XDATA HEX program to the CODE HEX program ? Is it possible or not? Thank for your reviewing .....
" Because the NOR flash can update data easily. If we put all the program in ROM, that would be some risk when production. Maybe we have to reclaim all the controller." Are you aware that there are a number of 8051 derivatives available with built-in bootloaders that allow you to easily change the firmware without removing the microcontroller from the circuit?