PARTS REQUIRED TO MAKE ONE DRO INTERFACE WITHOUT USING
AN INTERRUPT.

Look at this list together with no_irq1.gif, no_irq2.gif,
and all five of the box.jpg files to see how these parts 
go together.

From Mouser Electronics    Catalog #585
800 346 6873

QTY.		DISCRIPTION					PRICE
1	156-1426   25pin D-Subminature		page 116	$.73
2	534-7231   screws for 25pin connector	page 120	$.34
10	156-1402   Crimp pins for above		page 116	$.10
1	400-5053  4.19x2.74x1.57 box		page 272	$3.73
1	400-7053  4.02x2.56 lid for above	page 272	$2.63
4	534-720  Rubber feet for box		page 277	$.18
6	PNP Transistor 33-KN2907		page 19		$.18
1	1055-TA1120   switch			page 222	$1.45
1	400-9053 pre-punched pcb board fits box page 272	$5.06
1	571-14804260 pc power supply plug	page 127	$.40
1	571-3505471 pin for above need just 1	page 128	$.09
1	566-8723-100   cable (belden #8723)	page 74		$28.00 *
1	515-2064-12-03  100' 18AWG 	wire	page 80		$7.06  **
1	140-CD50Q9-104Z   .1 µF Capacitor	page 190	$.18



*100 feet spool is the minimum that Mouser will sell.  You may be able to find
another source for this in just the length you need.  It is the wire that
runs from the encoders back to the box.  The cable contains 4 individually
shielded AWG 22 wire.  

* 100 foot spool is the minimum that Mouser will sell.  You may be able to find
another source for this in the length you need.  It is single strand insulated 
18 AWG wire.  You will need about a 2 feet longer piece than what your parallel 
port cable you will be using is.  This is to bring 5V out of your computer.  
If you plan to use a outside power source (other than you PC) for TTL 5V DC 
then this wire is not needed.


Hewlett Packard encoders suppliers:
800 235 0312    HP questions about their components
800 367 3573    Newark Electronics
516 434 7470    Hamilton Hallmark
www.usdigital.com   800 736 0194  (said they will have some linear encoders and
strips available soon for the price about the price of HP encoders).  They
also sell connector plugs and cables for HP encoders.


Hewlett Packard encoders part numbers:
HP makes lots of rotary encoders and some linear encoders (200 lpi).
The higher resolution ones are:

code wheel :HEDM-6120-U06 (this is a 2048 count per revolution)
module reader for above is: HEDS-9000-U00.  This module will also
read code wheel HEDG-6120-U06 (this is 2000 count per revolution).

The last two number of the code wheel HP # is the size of the shaft
hole diameter.
05 = 3/16
06 = 1/4
07 = 5/16
08 = 3/8
09 = 1/2
10 = 5/8
11 = 4mm
12 = 6mm
13 = 8mm

HP supplies just the module (reader) and code wheel.  You will have to make
your own housing.  Or contact www.usdigital.com as they sell them with and
without housing.

Not just HP encoders will work with DRO.  Any encoder that puts out a
low voltage quadrature square wave should work.