gub,
The demos are great. Out of curiosity, does the PETdisk respond properly to the BASIC 4 commands of "directory" or "catalog"?
-Dave
It does not at the moment. But I would like to support these in a future revision. Do you know how these commands work on the IEEE-488 bus? I could just watch these commands on the bus but would certainly be easier to implement if I knew the sequence. I've mainly been working from the "PET and the IEEE-488 interface" book, and these commands are not documented there.
Another upgrade which will go into the next revision will be support for long file names when saving files to the PETdisk.
Currently when saving a file to the PETdisk, you are limited to a short DOS filename (8.3), and since it gives every file a .prg extension, you're really limited to 8 characters. (i.e. 'SAVE "12345678",9) This limitation is only when saving a file - with loading you can read files with long filenames. This is because I currently have code that can read long file name attributes in the FAT32 file system, but do not have code to create such attributes yet. This is next on the agenda. You can, however, rename them with long file names on your computer after they are saved from the PET, and you can read them back with the long names.
The last revision I put into the firmware was support for hot-swapping SD cards - so you can remove a card from the PETdisk, change some files on your computer, then put it back in, and it will recognize the changes.
One other thing - I found this schematic for a very simple serial port AVR programmer. This looks equivalent to the link I posted earlier, but this is a homebrew version. A very simple way to get set up for programming AVR chips, if so inclined.
http://avrprogrammers.com/bld-dasa.php