From: asc135@yahoo.com   
      
   Bill Gunshannon wrote:   
   > I don't know about for others, but this is a major stumbling block for   
   > me now that I have started playing with my TRS80's again.  I know there   
   > are PC's that can read/write TRS80 format disks, but they are getting   
   > rarer all the time.  Heck, just finding a PC with a floppy controller   
   > is getting hard.  So, here's my real question.  Is it possible for a   
   > Tandy Color Computer to read/write TRS80 disks?  Has anyone written   
   > software to do this?  I would think that with something as powerful   
   > as OS/9 if the hardware was capable the software would not be that   
   > difficult.  Comments?   
   >   
   > bill   
   > (Who is buried in the snow and has the whole day to play with stuff   
   >  he actually likes to use!!)   
   >   
      
   Assuming you mean disks from the Z-80 family of TRS-80 machines, a CoCo   
   can read/write sectors from Model III and 4 disks since they also use   
   256 byte double density soft sector format. I'm not 100% sure if any of   
   the CoCo controllers are capable of FM encoding which is used in Model I   
   disks (even Model I double density disks since track 0 is single density   
   on those).   
      
   If CoCo controllers are FM capable, you'd be able to read any Model I   
   disks and could write all but Model I TRSDOS disks.  Those used a   
   non-standard data address mark on the directory track which can only be   
   written by the FD1771 controller used in the Model I Expansion Interface.   
      
   For the Model III and 4 case you could use the Color Disk BASIC (or   
   OS/9) sector I/O calls but for the Model I case you'd probably need to   
   write assembly language drivers to operate the controller directly in FM   
   mode.  I'm not familiar with the OS/9 diskette driver and whether or not   
   you can select the density directly.   
      
   Amardeep   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)