Long time listener, First time caller to Instructables!  
Welcome to my first Instructable!

This hack is a reuse of the old 40 pin SCSI cables.
I was tired of using breadboard space for loading up a bunch of resistors for driving a 128x64 display on microcontroller projects.

It turns out you can use a SCSI hard drive cable for conditioning signals from your device before it gets to the breadboard.
SCSI cables have 2 rows of 20 wire lines running from one of Female Headers to a middle Set of female headers to the other end of female headers.  Both rows are accessible at any of the headers.

The 128x64 LCD  I am using has 20 lines to attach to my breadboard.  I soak up alot of breadboard space conditioning these signal lines with resistors, potenetiometers or capacitors.  I decided to use the middle headers of the SCSI cable to add these components in.
Row 1 of one end of the SCSI cable attaches to the breadboard with header pins.  Row 2 of the other end attaches to my device, the 128x64 LCD.

I believe this has more potential to make projects more modular, perhaps by adding a small perfboard to the middle header for more conditioning of your data lines.

Step 1: Equipment

I wont go into detail about the microcontrollers, because I am using here a propeller, but this works well for Arduino or any other microcontroller project you are using.
Just note what voltage the reset pin of the LCD need to not constantly reset.  Some microcontroller pin outputs are only 3.3v
This oversight soaked up time in my troubleshooting, I eventually tied the reset pin (17 of the LCD) to 5 V.

For Equipment:
Your microcontroller of choice.
a Schematic of your connections(this came from the propeller obex.)
14  470 ohm resistors
20k single turn Potentiometer( I used a 10 K and seems to work fine)
40 Pin SCSI cable with a middle female header.
                             (prep the cable by taping the same side of each header with electrical tape, see the cable picture for more details.)
128x64 LCD display, I already soldered header pins to the LCD
Something to cut wire and excess leads,  and you might have to strip a wire.   These needle noise pliers with a cutting tool worked great.

i took sort of your idea, i have an old sound blaster card with a 2x20 pin array, connected one of these cables, and can now use other features on the card, it is a ct4830 card

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Bio: My favorite distraction is Learning and Tinkering.
More by Zachariah: Pythagoras Cylinder with Sketchup to STL Hacked SCSI Hard Drive Cable for 128x64 screens using microcontrollers
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