XL1 Mod List:
------------

Date(dd/mm/yr)          Modification
-------------           ------------

1) ??/03/96     Wire U15-pin33 to GND  (enable Xilinx as master).

2) ??/03/96 	Cut U16-pin3, connect this to pin to U16-pin4 (connect
		prom RESET/OE to DONE/PROGRAM).

[3) ??/03/96 	Pull Up resistor for DTACK (cause DAQ failure if XL1 cut
		from XL2).]
mod 3 is officially obsolete.

(this mod above is now part of mod 6 below.)

4) 25/04/96     Cut  U47 P1,9 and connect to GND (corrects inputs for LED 
						  one-shots)
		Cut  U52 P1,9 and connect to GND (ditto)
		Replace C10 (100pF) with 1uF (extends time constant RC)
		Replace R36 (10K) with 25 K

		similarly for other RCs of LED one-shots (see below.)

4a) 29/04/96	i.e., (continuation of above)

		Replace C6,C8,C9 (all 100pf) with 1uF
		Replace R33,34,35 (all 10K) with 25 K.


5) 1/05/96     Stuff R2 with 20k, and R3 with 27k.   This sets the STROBE
               delay and width.


6) 22/7/97     add 500 Ohm resistors pullapart on DTACK receiver.  U66, pins 9, 10.
	       U66, pin 9 to GND, pin 10 to VCC.