calibration switch

[tarmac terror]

I thought I'd seen the answer to this but having looked through the manual and searched the forum I came up with nothing...

Question is....
I have a 12-way rotary switch with each position being distinguished through reisitors. I'd like to utilise this for some high/med/low boost maps but I'm currently out of AV inputs. Am I right in thinking that I caould connect this up to the (currently spare) AT6 input? The switch terminates in 2 wires.

Logic seems to tell me that these are resistive inputs anyway so should work fine!!??

Just looking for clarification.


TT

[Scott@FP]

Yup. Only two wires needed, the switch resistor network takes place of a thermistor. Its the easier way of doing it really.

BTW 'shorting contact' multi-position switches work better, they don't bounce to either 0v or 5v in between positions.

[tarmac terror]

Thanks Scott.
So you mean something like this.......


http://uk.rs-online.com/web/p/rotary-switches/4407657/

????

Wouldn't that require an input for each switch position??

TT

[Scott@FP]

The center pole on your example is the common, for an AV input pin 1 would get 5v or 8v, pin 12 gets 0v, and the center pin is your AV input voltage. You just solder discrete resistors between pins 1-12 so when you switch, another resistor gets added (or subtracted). For an AT input you just hook up pin1 (or 12) and the common. If you wish to target a specific voltage for each position you will need to calculate the resistor needed via a voltage divider calculation. PM me your email and I will send you a spreadsheet for calculation of resistors needed for this 12 position switch into a Motec AT input.

Now you write a custom sensor user channel in sensor setup/input setup/user tab to use this, create a custom user channel sensor table, input is the voltage value in each switch position, lower row is the output value (switch position). When your switch is in various positions your new user table outputs the switch position 1-12, you can use this on any table axis.

[SprinterTRD]

Checkout drawing X26 on the MoTeC website, describes it all!

[Stephen Dean]

Link the the X26 file

[tarmac terror]

Thanks for the help there folks.

Was at this today and hooked up one wire to ECU 0V and the other to AT6. Had a look at the raw input screen and as I turn the switch to each position I get a corresponding change in the value so I think I've cracked it.

Just need to set up a table to take account of these values and it should all be good.


Thanks for the guidance


TT