Hi all! I m a SY E&C student. And m working on a microcontroller based project.The one i m using is AT89C2051. To test it i wrote a sample program and loaded it in the controller using a universal programmer. The sample program would write a low to P1.3 continuously using an infinite loop. but wen i started the controller after making all the external hardware connections(reset and crystal oscillator , Vcc and GND) instead of showing logic low it gives me +5V only at pin P1.3. Can anybody help me troubleshoot it?
The sample program ... Can anybody help me troubleshoot it if somebody could troubleshoot a program they can not see, that would be pure magic.
Till you show the code, nobody can help you
Erik
Time for mister ,berik to correct his name before making any more posts. You have spent the last week with this alias - how is it pronounciated?
and processed
Well the problem is, i think with the controller and not with the program.I mean what can b there with a 4-5 line code. Any way the code is org 0000h ljmp main org 0100h main: clr p1.3 sjmp main end
your code is fine
loaded it in the controller using a universal programmer did you use the right chip designation? did you verify? (if your programmer can not read a chip, it is worthless) (reset and crystal oscillator , Vcc and GND) is reset showing not active (look in the datasheet what level that is), is the oscillator running? what you see is (most likely) one of the below: the chip is held in reset the oscillator is not running the chip is not programmed
watchdog reset?