PIC refusing to program

Hi all,
I have been using a PIC16F628 for a project, programming it fairly often (only for a few days though) and it has been working fine. It seemed to be
misbehaving so I erased it, and now I can't program it again! This has happened before with a 16F84 but I can't remember how I fixed it.
I am using a programmer from oatley electronics which uses the parallel port, and David Tait's FPP software which reports "Failed to program code!" or "Failed to program config!". I think once I get the config programmed it will work but for now it wont do anything (code protected or something?). Reading the PIC, it won't tell me what the config workd currently is. I have tried other software too but it was hard to tell if it was set up properly because it was refusing to program anyway.
I have checked all the pins with an oscilloscope while programming and they are doing what they are supposed to, though the rising edges of clock and data are rather rounded. I haven't changed anything though, so I doubt that is the problem.
Any ideas would be much appreciated! - Daniel
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Hmmm. Just a thought.... It sounds like you may be having trouble with your voltage regulator. Have you checked its output under load?
BRW
On Sat, 2 Aug 2003 22:16:42 +1000, "Daniel Watman"

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