Hello I need to do a simple program that blinks a LED located on pin 3.4 on a winbond w78c438c. In a uvision simulation everything goes ok...but when I try it on the actual board nothing happenes. What could be the problem? I used generic settings: reg52.h/ variables in xdata ...
the actual board has power... this is known in 2 ways: -the power led (connected between 5v - resistor and ground) -a change in the whisleing sound made by the power supply (a prestabilised power supply that does not enter in limitations)... The TEST led sh. blink but remains on (acc. to initial value after power up). In simulations I obtain a change in p3 value each 500msec(led blink rate 2Hz), so there isn't a possibility of higher rate than the human eye can perceive. I had a simmilar problem once when I used a combination of IAR EW and msp430. Then the problem was in project/target configuration...and that is hat I suspect...but I think I didn't forget anything.
Also the program is loaded onto a EPROM which is checked before and after write by the software program of the universal programmer.
the actual board has power... totally irrelevant info, that the "board has power" does not mean that the uC does. The TEST led sh. blink but remains on How is the LED connected port pin high or low ro light it? In simulations I obtain a change in p3 value each 500msec how do you know "500msec", the simulator is not "real time". If the output changes at more than 100Hz, the LED will seem steady Also the program is loaded onto a EPROM which is checked before and after write by the software program of the universal programmer. irrelevant, how do you know that the EPRON is read by the uC Get the scope out and start looking qt the uC pins Erik PS does anyone still use EPROM for code storage?