Recent content by Dwight Elvey

It is common to use current through the capacitor and look for heat. We used to get thermal paper ( actually plastic with liquid crystal that was sensitive to heat ) and place it over the board an look for hot spots. The thermal cameras that one can plug into a cell phone are sensitive to...

I believe it is PCOS. Dwight

What interface did you use to program it? I know some of the other chips require one to use a 5V RS232 signals and not the typical higher voltage RS232 signals. I'm not that familiar with the PIC parts. Dwight

I have an older Canon and I will put it up against anything my wife takes with her latest I-phone. Even she goes the real camera when expecting a quality picture but likes to snap the quick picture with her phone. Of course, you can use the supper 200X slip on lens on your cell phone, designed...

I've not done a Z80 but I usually just look for absolute jump instructions first. Most code rarely jumps out of its own memory. Look for the possible target locations. Look to see if the target location makes sense. In other words that it doesn't look like the middle of an instruction. Another...

Are all old MFM drives bad? When I wanted to add a hard drive to my NC4000 processor ( and I'm cheap ) I bought 3 ST506's at $5 each. I accidentally damaged one ( never rotate the spindle backwards ). Now I have 2 have these drives. I got an old XT 8 bit MFM controller ( for a few dollars ) and...

I use a EEPROM for my KIM-1 6530 replacement. It does have a write enable pin but I've no felt the need to use the hardware protection. Not only does it seem to have a robust sequence to actually program but for reasons related to the small space that I allotted to it, both the address and data...

I'm with Chuck. Not in my drives, thank you. They typically leave gobs that need to dry after using that could break lose and damage you disk or drive. You don't really know when you are done or use them two long. They are especially dangerous for many double sided drives. Get swabs with long...

I've never used one in a floppy drive. Cleaning is why swaps were created. Dwight

Its too bad it was the -002 that was bad. That one is needed to boot. The -003 code is only for I/O. It otherwise could be used for a number of Butterwoth's games. Good to see it working. Dwight

There are a couple ways. You need a florescent lamp that isn't one of the new ones. They use a high frequency and not 60 HZ, so CFL are not too good for this. I suspect an incandescent lamp with a really thin filament might work but never tried it. Something like the lamps used for sowing...

Yes, a reader but no floppy drive on the system. Anyway, a great number of interesting tapes to read. There are two ways the NIC-80 can read tapes,depending on the reader. It can do it serially with rs232 or using the parallel bus input, depending on the reader. gnupubic, you should open the...

You have a lot of floppy tapes but I see no floppy drive. I do have the drive and interface. I have one hard drive and interface. There are so many great tapes you have. WOW!. Your find is fantastic. I don't see the floppy DEMON, just a lot of applications. Be careful with the core memory...

There was one thing that you might want to include. I saw this in a printer driver code I disassemble a while back. The conditional jump instruction can be used for what I call as a SKIP instruction ( that is what I put in my disassembler ). What this is is the set the condition bits so that it...

I stand corrected. I complement both the value and the CARRY before the ADD I do not complement the CARRY when done. Extracting from my code, it is ( in Forth) Reg@ $0F XOR Carry @ 1 XOR + ACC + DUP $10 AND $10 / TO CARRY $0F AND TO ACC Dwight