PATT03 Board Appendix		2/28/02
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This appendix gives a very brief description of the PATT03 board.
The PATT03 board is a revised version of the PATT02 board described 
in the Test Setup Note. It was developed specifically for use in a 
burn-in system. The board incorporates ttwo new features:

1) Loopback Mode:

After a pattern finishes running , the board senses the end of the 
pattern and automatically rewinds the pattern FIFOs and starts the 
pattern over. In the PATT02 board the pattern FIFOs can only be 
rewound by the RETRANSMIT control signal. In the PATT03 board 
RETRANSMIT serves no purpose. 

2) Connections for multi-channel scrambler address bits:
 
The data connector of the PATT03 board has 3 static bits on 3 previously
unused pins. These bits select which port of a multi-port scrambler 
broad (in a burn-in system) has control of the data output bus.  

There are different software routines in the CPATT library (OUT.C 
functions) that are used depending on whether one has a PATT02 or a 
PATT)3 board in the system. If a PATT)2 board is used after loading 
a pattern the command out_run() will cause the pattern to run once
and will then rewind the pattern FIFOs to leave the board ready for 
another out_run() command. This command should not be used with the 
PATT)3 board. Instead, the commands out_go(t) and out_stop() must
be used. Out_go(t) will cause the PATT)3 board to run the pattern
over and over for a length of time t. If t is very small, eg. 1, the 
pattern will only have time run once. The full pattern will run though. 
If t=0 then the pattern will run again and again indefinitely. The 
command out_stop() must be used to stop the pattern in this case.  

The pin assignments of the connectors on the PATT03 board are the 
same as on the PATT02 board, except for the 3 address bits on 
previously unused pins of the data connector.