3
18.
Power up your TI-99/4 or TI-99/4A computer
Wiring Diagram
Some signals must be paired with a ground singnal. It easiest to tie all grounds
together by soldering one connector side of the grounds to the DB37 metal housing.
Also some signals must be away from others in order for the inteface card to work
correctly. Please follow the color codes below as they have been proven to work. Photos of
a finished cable end is at the bottom of the document to help better identify what colors are
what.
Using the recommended 50 pair twisted pair double shielded cable allows for only one side
of the grounds to have to be connected because along with the shield ground wire connected
to the metal housing then all become grounded since the 838-IO Plus boards DB37 mounting
poins are also grounded in the circuit.
When the cable is complete you should have 49 conne shield ground wire.
DB37 Male
Wire Pair Colors
Pin #
Signal
1 +8VCC
Red - White Stripe
2 MEMEN
Pink - Purple Stripe
GND
Pink - Red Stripe
3 CRUIN
Mint Green
–
Blue Stripe
GND
Green - White Stripe
