Why? Because what you're trying to do is outside spec, highly unusual, and unlikely to succeed with the equipment you have on hand. Furthermore, you're trying to solve a problem that the chip manufacturers themselves solved with ISP years ago.


As for $15 CDN... The AT89S52 in 40 pdip, which is likely a 100% pin compatable replacement for your chip, is $2.01 USD at Digikey, which is about $2.38 CDN today. It will run at 33Mhz, so your 18.432Mhz xtal is well within spec. It's serial programmable, via FLIP. All you have to do is buffer your parallel port and/or keep the leads short. Mouser has the 24Mhz version for $3.10 but are out of stock. They have a better small order policy. (Erik will be along shortly with the NXP equivelent part, so I won't bother looking it up... :-)


As for using what I have on hand... All the time. I started dabbling with electronics when I was in the 3rd grade. I've got a junk box that's 30+ years deep. You know what? Most of it is junk! Anyone need a JAN 807 tube? I have some mid-60's transistors too. We're talking 2N1304's and 1305's in big metal cans, 2N711's. Probably not RoHS... :-)


~2 years ago when I first found this site, I was in the same boat. I had an eprom programmer, a bunch of 8031's and a big pile of 2716's left over from 1984. The crew here gave me the same advice, which I've been slowly taking. Sometimes you just have to bite the bullet and buy the right part.


Rob