Thread: New Project Help

Originally Posted by quick503

...Phone # of a good shrinK

1-800-nuts-r-us

Seriously, that is an ambitious project. I don't have anything to offer as far as coding goes, but I do have a suggestion.

You might consider some sort of throttle-limit switch just in case of a missed shift. That would keep you from spilling 302 guts all over the road due to over-revving (translate: been there, done that).

I use a FB to control steering on a farm tractor. I have two relays, each going to one side of a solenoid that controls a hydraulic valve. I also have a sensor to tell me what angle the steer axle is currently at. All I do is feed a target steer angle to the logic and it will issue left or right commands to get the steer axle to that target point.

Personally, I'd use two potentiometers to determine where the shifter is currently. Seems easier to read two inputs to determine the location than to read through the 6 switches.

Over Rev protection sounds like a great idea (not that I have EVER missed a shift ).
Using pots sounds like a good idea. I just wonder how temperature will effect the readings. The temperatures could go from below freezing to 150 degrees or so.

I know I'm getting this wrong. Can someone point me in the right direction? I want to use an analog input to turn the output on or off. If the analog input "sees" more than 4v (but less than 5v) then the output would turn ON ... less than 4v then OFF.
This is what I have so far.

<!-- Begin Digital Output Instances -->
<iochannel id="Output0" port="0" brain="My Fusion Brain 0" type="digital_output">
<defaults defaultstate="off"></defaults>
</iochannel>
<!-- End Digital Output Instances -->

<!-- Begin Analogue Input Instances -->
<iochannel id="Input0" port="0" brain="My Fusion Brain 0" type="analogue_input">
<options history="0" auto_average="false"></options>
</iochannel>
<!-- End Analogue Input Instances -->
</io>

<logic>
<!-- Begin Logging Setup -->
<all_logging>
</all_logging>
<!-- End Logging Setup -->

<!-- Begin Variable Declarations -->
<all_variables>
<variable name="Variable_Analogue_Input_0">0</variable>
</all_variables>
<!-- End Variable Declarations -->

<!-- Begin Logic Declarations -->
<all_statements>
<if fire_on="logic" minimum_delta_vote_time="100" id="Logic for Analogue Input 0">
<parameter1>
<boolean_operation type="greater than">
<parameter1>
<variable do="get" name="Variable_Analogue_Input_0">
</parameter1>
<parameter2>
<number>4</number>
</parameter2>
</boolean_operation>
</parameter1>


</if>
</all_statements>
<!-- End Logic Declarations -->
</logic>

Couple of more questions. If I change the software by editing the xml file when does it take effect? Do I need to remove power from the FB (reboot it)/
If I use the configurator to add just a digital output to be default "ON" should I be able to read 12v on the output pins?
Thanks

You are on the right track, but you want "if input X is greater than Y volts", and what you have is "if variable Z is greater than Y volts".

So change that variable to the input you want. Also are you editing that manually?

All that statement will then do is check if the input is greater than 4v. If it is or isnt, it will go woohoo and move to the next statement. To make it turn on/off an input you will need to add some then and antithens.

So the then would be when it evaluates true, so turn output ON.
The Antithen would be when it evaluates to false, so turn output OFF.

Originally Posted by quick503

Couple of more questions. If I change the software by editing the xml file when does it take effect? Do I need to remove power from the FB (reboot it)/
If I use the configurator to add just a digital output to be default "ON" should I be able to read 12v on the output pins?
Thanks

To make changes all you need to do is restart MDX.

If you make an output have default on, then as soon as MDX starts, that output will turn on. The LED will light if the jumper has not been removed. The output pins will be whatever power voltage on the DC Jack all the time (regardless of output state). If you are powering via USB, and have no DC jack connected, no voltage will appear on the output pins. When an output turns on, the ground pin activates and completes the circuit turning things on.

I just tried using the configurator and Ninja Kitty to make an xml file. I added the Fusion Brain and one digital output. I set the default state to ON but it wouldn't keep the setting so I edited it manually. I started MDX but no light. I do have the 12v power supply attached. I need to get this to work so I can have someplace I can go to to say "I know this works" when trouble shooting. Do you have any experience using opti sensors? Also can I use the 5v pin on the analog input to drive the signal high?

OK, I used this in the Logic area and it worked.

<all_statements>
<if fire_on="logic" minimum_delta_vote_time="100" id="Root Function #">
<boolean_operation type="greater than">
<parameter1>
<analogue id="SC1" time="0"></analogue>
</parameter1>
<parameter2>
<number>4</number>
</parameter2>
</boolean_operation>
<then>
<do function="Trigger Output" functionTargetID="D0" vote_opinion="On" vote_priority="High"></do>
</then>
</if>
</all_statements>

I can't seem to figure out how to get the anti-then part. Do you do another <if>, </if> section but use "not"?

<if fire_on="logic" minimum_delta_vote_time="100" id="Root Function #">
<boolean_operation type="not">
<parameter1>
<boolean_operation type="greater than">
<parameter1>
<analogue id="SC1" time="0"></analogue>
</parameter1>
<parameter2>
<number>4</number>
</parameter2>
</boolean_operation>
<then>
<do function="Trigger Output" functionTargetID="D0" vote_opinion="off" vote_priority="High"></do>
</then>
</if>