Apple II

I recently came across some old Apple II cassette tapes I apparently created back in 1979 or 80.  One of the cassettes had files on both sides.  The contents were:

Side 11. Othello (2 copies each)2. State Capitals (2 copies each)3. Advanced Dragon Maze (1 copy)

Side 21. The Applelodion (2 copies each)2. Appleodion Data (2 copies each)3. Two Voice Music Data (2 copies each)4. Bach (1 copy)

Hi!  Over the past few days, I delayed work on printtok2 in favor of a slightly improved version of printtok1.  The new features include 128 one-byte tokens and more special control codes, including pauses, clear screen, inverse mode and, for most CBM targets, up to eight text colors as stored in an array in the modules.  It still doesn't have automatic compression, but I'm working on it.  It is at https://sourceforge.net/projects/cc65extra/files/ui/.  Try it out!

I am occasionally getting an IO ERROR when executing commands, even when I successfully executed other commands before it gave me the error. If I check the kernel using CLOSED APPLE+CONTROL+RESET, it gives me the error message "IOU FLAG E5:1". If I check the kernel using the same method before the IO ERROR message appears in the console, the diagnostics tool tells me KERNEL OK. 

I am trying to fix an external Disk /// drive that gives a "Format error #21. Internal program error." Message when I try to format a diskette. When I format the diskette using the internal disk drive, the disk completes formatting with no errors. I've looked through my Apple /// manuals and did a Google search, but cannot find what this error means. I've cleaned the head on this disk drive, have cleaned the head mechanism rails with isopropyl alcohol, and have replaced the ICs on the Disk /// Analog Card from a known working Disk II drive.