Thread: Auto Climate Control

We would be willing to help. Depending on the complexity, we may have to charge a consulting fee, based on time involved in determining a solution.

There is no way to get more outputs without another brain at this point. You could check the discounted brain out here:

http://www.fusioncontrolcentre.com/F...products_id=55

If you specify you need all 12 outputs working we'll be sure to test that. Generally it's just a bad LED on the board.

... Or you could mutiplex and latch a few of the outputs this will surely work. Though in the software you would have to select a channel then activate it, opposed to just turning one bit on.

You could do something like what I have done, to send a different voltage to a single analog input for each of several buttons. My work is set up for 32, but you can do any. But from scratch, it's cost me a little more than the price of a new brain. The parts cost about 25$ total, not including getting a custom prototype PCB made, but it can be done more cheap. Also, you may get unexpected results (press defrost plus recirc, and the compressor may turn on ) if you press more than one button at the same time.

As for the servo/PWM route, you're going to need to do one of a few things:

a. wait for an analog output from the fusion dudes.... and keep in mind, when taking a parallel style output device and providing an analog output, you will sacrafice a few outputs, who's quantity will vary depending on the resolution required, and what's available.
b. build/find something that can drive PWM....

c. find a servo that does not require an analog input. They do exist. Basically one voltage level will drive the motor in the open direction, another will drive it closed. Then, with a PBR (position sensing potentiometer) sending an analog feedback signal, FCC can be taught to stop the motor (yet another voltage) when the feedback resistance (and thus it's voltage) is at the pre-assigned level for that particular position. GM makes these, for just this application. The voltages can be created with just a couple digital outputs and a few resistors.

Exactly, do not buy another brain if you can accomplish this using one. There are multiple ways, multiplexing/charlieplexing/etc! You can do analog-digital circuits or the like and they will cost less than 25 bucks if you do it on the cheap

imgoingforit,
Can you post a pic of your climate just so I can see how the buttons are configured. Im sure I could give you a lead to multiplexing your outputs. As some climate systems have tactile buttons or buttons that stay down when pressed, the solution for each of these systems would be different. If I were you I would get a digital servo (one of those 15Kg ones) and mount it on a bracket and connect it to your cable drive. If you do this I will come up with a servo controller for you.

So based on that post, 15kg would be good for the servo?

Yep, thats what I found. I also noticed that you can gain more power from a servo when you drive it at a progressive pulsing mode. Its hard to explain but basically a normal servo moves from position 'A' to position 'B' as quickly as it can. If you control the servo to move between positions slowly (this is done by gradually increasing the pulse width) much more power can be gained, the movement it also not as noisy.