I am trying to write a c program in keil, which interfaces with assembler functions. I have managed to allow the c program to call these functions but i'm unsure of how to pass arguments between them. My assembler function is as follows. However, i wish to replace the #55h with an argument from the function call in c. ?PR?write_text?WRITE_TEXT SEGMENT CODE PUBLIC write_text RSEG ?PR?write_text?WRITE_TEXT write_text: SETB EN SETB RW MOV CMD,#55h CLR EN ACALL WAIT_LCD RET Any help would be much appreciated. Thank You, Tim Wood