Nothing to report on the floppy side of things. Still need to sit down for a few hours to study the sector with the wildly varying bit cells.
On another note I have just bought a DIP42 adapter for the EPROM programmer. This allows me to program 27C400 chips which appear to be pin compatible with the Amiga Kickstart. An idea I had some time ago was to develop a diagnostics ROM to dump information out the the serial port. You’d use this in “dead” Amigas, say for example a chip ram IC was duff; this util would pump out the memory test results to the serial port. (Basically stick it in a machine that won’t boot and hopefully find out what is wrong…)
Anyway, the first thing is to check to make sure all is OK and to do that I simply attempted to make a backup of my Kickstart.
Sourced some 27C400-105DC chips (thanks again eBay). I inserted the Kickstart chip into the programmer an did a read operation. Data looked great. Stuck in the 27C400 and hit program. It took a couple of minutes but the result was perfect, the thing verified OK. Inserted in the A2000 and away it went…
Small point worth noting is that if you’re programming from a ROM from, say, WinUAE you need to change the endianness by swapping around the bytes of each 16 bit word before programming (infact this feature was a part of the programming software so happy days).