Hi, i'm a newcommer to the world microcontrollers and started on my first (hopefully of may) pic project for my final year in university, using the PIC16F877. The project involves creating a 'laser' targeting system for model aircraft. I have used infrared techniques used in lazer quest games for the system coupled with a nice pair of tranceiver modules and an LCD.
Anyway, after months researching and designing the code, all was good. I write the code in CCS and modeled my design (well the LCD anyway) in proteus VSM and it worked great. Finally last week i committed my design to silicone, before placing in my PCB only for nothing to happen!! :-(.
The LCD just produced 20 black squres and nothing else. On trying to debug i found that i had used 33uf instead of pf oscillator capacitors and changed them. Still nothing. So on the advice of one of the techs i wrote basic code just to turn on and off LEDs attached to portA. This seemed to work on the ICD demo board, but again not in my PCB?
After reading the notes for the forum i realise the LED on RA4 wouldnt work anyway because it is open drain type but i dont know why the rest dont. I have disabled the analogue inputs and made sure the tris is correct. There deffinately is 5V to the PIC. Do you think i could have damaged the 4Mz Xtal (XT setting) with the wrong caps? Maybe that would explain why nothing is happening. I am REALLY lost now. Even the uni tech couldnt help. So if one of you can, or has any advice, please, please help!!!....
Ross
Anyway, after months researching and designing the code, all was good. I write the code in CCS and modeled my design (well the LCD anyway) in proteus VSM and it worked great. Finally last week i committed my design to silicone, before placing in my PCB only for nothing to happen!! :-(.
The LCD just produced 20 black squres and nothing else. On trying to debug i found that i had used 33uf instead of pf oscillator capacitors and changed them. Still nothing. So on the advice of one of the techs i wrote basic code just to turn on and off LEDs attached to portA. This seemed to work on the ICD demo board, but again not in my PCB?
After reading the notes for the forum i realise the LED on RA4 wouldnt work anyway because it is open drain type but i dont know why the rest dont. I have disabled the analogue inputs and made sure the tris is correct. There deffinately is 5V to the PIC. Do you think i could have damaged the 4Mz Xtal (XT setting) with the wrong caps? Maybe that would explain why nothing is happening. I am REALLY lost now. Even the uni tech couldnt help. So if one of you can, or has any advice, please, please help!!!....
Ross