Need pinout for tether adaptor

Posted by Paul Michalczuk, Student on team #217, Team Macomb, from Cousino and Ford.

Posted on 2/28/99 7:56 PM MST

Help! I need to know if the tether adaptor that came with the kit is basically a gender changer or do I have to make a connector box for it?? If i have to make one, anyone know the pinouts??? I seemed to have misplaced it.

Thanks in advance.

Posted by Jeremy M. Husic, Engineer on team #47, Chief Delphi, from Ponitac Central High School and Delphi Automotive Systems.

Posted on 3/1/99 9:57 AM MST

In Reply to: Need pinout for tether adaptor posted by Paul Michalczuk on 2/28/99 7:56 PM MST:

: Help! I need to know if the tether adaptor that came with the kit is basically a gender changer or do I have to make a connector box for it?? If i have to make one, anyone know the pinouts??? I seemed to have misplaced it.
: Thanks in advance.

The tether adaptor passes three pins between two 9-pin D-Sub female
connectors. The pin map is as follows:

1 Not connected between the two connectors
2-------3 Note flipping of pins!
3-------2 Note flipping of pins!
4 Not connected between the two connectors
5-------5 Ground pass through
6 Not connected between the two connectors
7 Not connected between the two connectors
8 Not connected between the two connectors
9 Not connected between the two connectors

Hopes this helps.

Posted by Jeremy M. Husic, Engineer on team #47, Chief Delphi, from Ponitac Central High School and Delphi Automotive Systems.

Posted on 3/1/99 11:36 AM MST

In Reply to: Need pinout for tether adaptor posted by Paul Michalczuk on 2/28/99 7:56 PM MST:

: Help! I need to know if the tether adaptor that came with the kit is basically a gender changer or do I have to make a connector box for it?? If i have to make one, anyone know the pinouts??? I seemed to have misplaced it.
: Thanks in advance.

If you do not want to make it, you can buy an equivalent at Radio Shack.
Since the FIRST adaptor is really acting as a null modem adaptor and
gender changer, you can buy both at Radio Shack: null modem adaptor
DB9 male/DB9 female (part #26-264) and gender changer DB9 female/DB9
female (part #26-266).

Unfortunatly Radio Shack does not sell a null modem adaptor female /
female, which is really the FIRST adaptor.

Posted by Eric Rasmussen, Engineer on team #-1.5 from FIRST.

Posted on 3/1/99 6:53 PM MST

In Reply to: Re: Need pinout for tether adaptor posted by Jeremy M. Husic on 3/1/99 11:36 AM MST:

: : Help! I need to know if the tether adaptor that came with the kit is basically a gender changer or do I have to make a connector box for it?? If i have to make one, anyone know the pinouts??? I seemed to have misplaced it.
: : Thanks in advance.

: If you do not want to make it, you can buy an equivalent at Radio Shack.
: Since the FIRST adaptor is really acting as a null modem adaptor and
: gender changer, you can buy both at Radio Shack: null modem adaptor
: DB9 male/DB9 female (part #26-264) and gender changer DB9 female/DB9
: female (part #26-266).

: Unfortunatly Radio Shack does not sell a null modem adaptor female /
: female, which is really the FIRST adaptor.

No no no! The tether adapter is only the same as a null modem adapter in concept. Pin 4 on both the Transmitter Box and Receiver Box is the power output for the RNets. If you use a standard Null Modem Adapter, you risk connecting pin 4 to something not designed to sink > 1A of current.

Please use only an adapter with the correct wiring. The correct wiring (pin to pin) is:

2 -> 3
3 -> 2
5 -> 5

That is all there is to the tether adapter.

Posted by Joe Johnson, Engineer on team #47, Chief Delphi, from Pontiac Central High School and Delphi Automotive Systems.

Posted on 3/3/99 8:02 PM MST

In Reply to: Tether Adapter is not a standard Null Modem Adapter! posted by Eric Rasmussen on 3/1/99 6:53 PM MST:

Yes, never do anything with the control system that FIRST does not okay first.

Yes, the an standard null modem and gender changer from Radio Shack work in a pinch (and I didn’t say this).

One time we were in some kind of a jam where we needed the robot to run under tethered operation and we did not have the proper adapter. Without asking, someone on our team “just did it” and cobbled up the gender adaptor/null modem combo Jeremy described. Everything was working before we had a chance to worry about it.

Since then, I have spent a bit of time reverse engineering the FIRST transmitter/reciever boxes. As I recall (and again, I am NOT advocating this) the pin that Eric is worried about is pin 4 on the 9 pin D-sub connection for the radio that is normally at 7.5 volts on the transmitter or 13.7 volts on the receiver. Anyway, I think that the null modem/gender changer combo routes each pin 4 to pins 9 & 1 on the opposite end. Happily, pins 1 and 9 do not especially care what is connected to them because as I recall, they are not used by either the transmitter or the receiver.

Anyway…

Don’t try this at home.

Joe J.