How to reprogram the L1D FLEX Proms
(aka the "Atmel chips")

Don't attempt any of this unless you know what you are doing and have been
blessed by the trigger group.

1) Create the new chip design using the Altera MAX tools 
(being careful to maintain the same device and pin assignments).

2) The Altera compiler will produce a file with extension "hex".  This is the 
file that you want to put into the appropriate prom on the L1D board. 
FTP (in ascii mode) the "hex" file to /home/trigger3/proms/l1d/ and give 
it the appropriate name. The name format is as follows: bxcy_version.hex 

where x is the board number (usually 1 or 2), 
      y is the chip number (0,1,2,3,4,5,6,7 for A1,A2,A3,A4,B1,B2,C1,C2, etc)
and version is the version number of the Altera design (usually the date it was produced,
(a number like 062202 for June/22/2002 for example).

3)Use the Prom submenu in the GenTest program to program and/or verify the proms. 
 - When asked for number of kBytes to program, use 256.
 - The chip numbering scheme is the same as above (A1 is 0, A2 is 1 etc).
 - When verifying, make sure to "cd" to a directory where you have write access.
 - When you verify you may get an error in the first byte...if this is the only problem don't worry.
 - You need to reset the crate in order to have the new program take effect 
   (**actually, you may need to cycle the power**)

4) Since all old file versions are left in this directory, we also keep a copy of the "current"
version of all chips (i.e. the one you just FTP'd) with a simpler file name indicating that this is
currently in use.  Make a copy of bxcy_version.hex to bxcy.hex. In this way, one can always tell
which hex file is current for each chip.