Hello all
I'm new to the whole microcontroller scene. I just built, according to a kit (**broken link removed**), a very simple PIC programmer and test board. This was designed for and supplied with a PIC30F84A, which I understand to be and old but faithful member of the PIC family and a suitable starting platform.
Anyway, I built the circuit as per the instructions. Then I ran the (very basic) send program which is supposed to take my assembled program (currently using a supplied example program as advised to) and sends it, via the parallel port, to the PIC. Then the PIC, once brought out of program/verify mode, is supposed to light up a couple of LEDs that are directly wired to its B port.
But... it doesn't. The PIC apparently does nothing. All I/O ports remain low during runtime. Since I'm using a very simple programmer, there's no obvious way I can see to tell where the problem lies - whether it is during the programming or the runtime.
As far as I can tell, the hardware is fine. All solder joints are good and continuity tests show now problems anywhere. Power is being supplied at the appropriate pins. While in program/verify mode, the voltage at MLCR is just shy of 12v, when switched to runtime mode, 5v. There is a RC clock input at the oscillator in pin.
My problem is that I really can't see how to diagnose this problem. I personally suspect the problem lies with the PC's LPT port used for the interface; neither the clock nor data pins used change in the slightest when the program is supposedly being transferred (using an oscilloscope to monitor), they both seem to sit at around 5v, although this might be all I'd be able to see.
There is only one problem I can see at the moment (seems unlikely somehow). The programming voltage is not quite in the 12-14v range. It's hovering at 11.9v, which I figure is close enough... is this a bad assumption? I'm planning to get a more powerful supply tomorrow to push it a little further but I'm not optimistic.
The design is that of EPE magasine 1998. I'm using the "PIC16F84 Programmer" by Derren Crome as my software send program, and I run its PIC configuration wizard, but similarly I have no idea if it's working. I've attached my program listing, I'm wondering if there's a simpler program, but I'm not yet understanding this code and don't feel up to changing it just yet...
Any ideas on how to test and work out what's wrong?
Cheers!
I'm new to the whole microcontroller scene. I just built, according to a kit (**broken link removed**), a very simple PIC programmer and test board. This was designed for and supplied with a PIC30F84A, which I understand to be and old but faithful member of the PIC family and a suitable starting platform.
Anyway, I built the circuit as per the instructions. Then I ran the (very basic) send program which is supposed to take my assembled program (currently using a supplied example program as advised to) and sends it, via the parallel port, to the PIC. Then the PIC, once brought out of program/verify mode, is supposed to light up a couple of LEDs that are directly wired to its B port.
But... it doesn't. The PIC apparently does nothing. All I/O ports remain low during runtime. Since I'm using a very simple programmer, there's no obvious way I can see to tell where the problem lies - whether it is during the programming or the runtime.
As far as I can tell, the hardware is fine. All solder joints are good and continuity tests show now problems anywhere. Power is being supplied at the appropriate pins. While in program/verify mode, the voltage at MLCR is just shy of 12v, when switched to runtime mode, 5v. There is a RC clock input at the oscillator in pin.
My problem is that I really can't see how to diagnose this problem. I personally suspect the problem lies with the PC's LPT port used for the interface; neither the clock nor data pins used change in the slightest when the program is supposedly being transferred (using an oscilloscope to monitor), they both seem to sit at around 5v, although this might be all I'd be able to see.
There is only one problem I can see at the moment (seems unlikely somehow). The programming voltage is not quite in the 12-14v range. It's hovering at 11.9v, which I figure is close enough... is this a bad assumption? I'm planning to get a more powerful supply tomorrow to push it a little further but I'm not optimistic.
The design is that of EPE magasine 1998. I'm using the "PIC16F84 Programmer" by Derren Crome as my software send program, and I run its PIC configuration wizard, but similarly I have no idea if it's working. I've attached my program listing, I'm wondering if there's a simpler program, but I'm not yet understanding this code and don't feel up to changing it just yet...
Any ideas on how to test and work out what's wrong?
Cheers!