ooops,

There is something wrong in the code:

Here we have three lines:

VAL EQU 00FFh ;value to be written

MOV A, VAL

DJNZ VAL, WR_MEM ;decrement

Is VAL value or memory location? If it is value then you need to use #VAL but then DJNZ VAL, WR_MEM has no sense. If it is memory location then why did you comment it as "value to be written"?

Regards,
Oleg