KansaiRobot
Member
Hello
I would really appreciate if you can tell me please any idea you get by the following situation. (I really need help )
I have soldered a socket to a perfboard, and put a 18F2550 in it. I have also soldered a circuit in it in which I use pin RB0~RB4. I also soldered RB6,7 to connect to the programmer. I have soldered other necessary components.
The program I wrote basically gives 1s or 0s to pins B0 to B4. nothing else.
I have successfully program the PIC.
Then when I power the PIC sometimes it works, sometimes it doesn't. If it works it keeps working good until turn off (there is no instability)
When it doesnt, a small push in the side of the PIC makes it work. Investigating more, when it does not work a touch with a metal to the PIN B5 makes it work. if it is working it makes it not work again!!!
Now I suspect about the soldering. however here is the strange and bewildering fact:
I used a oscilloscope to test the PINs directly.(Not the soldered connections) Pin Vdd is receiving 5V successfully. However Pins B0 to B4 are not outputing anything!
If I touch B5 they start.
So It is not the soldering or the connections!!!
What is happening here? Any idea? really any idea?
I have run out of possible solutions!
I would really appreciate if you can tell me please any idea you get by the following situation. (I really need help )
I have soldered a socket to a perfboard, and put a 18F2550 in it. I have also soldered a circuit in it in which I use pin RB0~RB4. I also soldered RB6,7 to connect to the programmer. I have soldered other necessary components.
The program I wrote basically gives 1s or 0s to pins B0 to B4. nothing else.
I have successfully program the PIC.
Then when I power the PIC sometimes it works, sometimes it doesn't. If it works it keeps working good until turn off (there is no instability)
When it doesnt, a small push in the side of the PIC makes it work. Investigating more, when it does not work a touch with a metal to the PIN B5 makes it work. if it is working it makes it not work again!!!
Now I suspect about the soldering. however here is the strange and bewildering fact:
I used a oscilloscope to test the PINs directly.(Not the soldered connections) Pin Vdd is receiving 5V successfully. However Pins B0 to B4 are not outputing anything!
If I touch B5 they start.
So It is not the soldering or the connections!!!
What is happening here? Any idea? really any idea?
I have run out of possible solutions!
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