Cloning a Tandy TRS-80 Model 1

[eshazen]

Just stumbled on this.  What a great piece of work!  I've been dreaming for a while about a TRS-80 clone.  My original still collects dust in a friend's attic half way across the country, but I would expect it would need some work to get running again.  One thing which stopped me was that I would really like to run a DOS (NEWDOS-80 was my favorite) on physical floppy disks, but (re-)designing a floppy controller seems like a lot of work, and probably most of my old floppies wouldn't be readable in any case.

Not sure if you're still checking the forum, but if you don't mind I have a few questions:

• If I wanted to build one are the gerber files on your website the latest and greatest?
• Any issues with the PS-2 keyboard for compatibility?  I recall a few games which used multiple keys pressed at once which might give trouble.
• Did you ever think about floppy emulation?

Just FYI my old TRS-80 had a long and happy life.  Started off with a 4K level 2 machine and upgraded it to 16k myself.  Then added the RS expansion interface which never worked reliably until I added a percom "doubler" which improved the floppy system quite a bit.  For a few years I ran TRS-DOS, then NEWDOS-80.  At some point the expansion interface got cooked (probably a power supply failure burned something) so I ditched it and replaced the 16K RAMs in the main unit with 64K ones with an I/O port controlled bit to rearrange the address space, disabling the ROM and putting the keyboard and video at the top of the Z80 space.   Then I added an "ICOM frugal floppy" controller with dual 8-inch disks and ran stock CP/M.  By this point I had added so many extra chips that I switched to a big rack-mount external power supply!  Probably the most amusing part of this was that to boot it you would start it in normal TRS-80 mode and load a small boot loader from cassette tape, which would boot CP/M!  At the end I think I added a small EPROM in one of the holes in the address space to automate the process.