Help with automatic relay control

Technical Programming
1

Forgive me if this is answered somewhere else – I looked and could not find.

I am trying to get a relay to automatically fire forward when the analog values to a pwm are in a range around nutral. I put an if statement in with an assignment specifying the condition I want and it works, but will not change states when when the joystick is moved out of the range. I tried adding an else if statement after, I tried a while loop, no good???

Any suggestions – I know it is something simple I am missing.

2

If you post your code, we can tell you what the problem is. If I understand what you are trying to do correctly, it should look a little like this:

if (pwm_val > (127 + deadband) || pwm_val < (127 - deadband))
{
relay = rev; // out of neutral condition
} else
{
relay = fwd; // in neutral condition
}
3

That is the first thing I tried, but the relay will not change from the first state it goes to.

I will try to post some code when I get to that computer. It is done in easyc though – I might just try to put in some user code.

Thanks

4

EasyC also visualizes as straight C code so you can post that. It could also be that your joy sticks are out of trim and moving them is not taking them out of your deadband.

5

I thought that also, so I did a print to screen and they show the value change.

6

Dan,

Thanks for the help. I got it working. I do not know what was wrong, but I redid it ( replaced || with && ) and it works great. By the way – this is for an automatic brake ( using a bicycle disk brake acuated pnumatically ) for our arm. I think it will work great now. Thanks !!!