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Mike Walne
Joined: 19 Feb 2004
Posts: 1785
Location: Boston Spa UK
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 Posted: Wed Dec 26, 2012 4:17 am |
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You're still ignoring most of the advice you've been given and the requests for more information.
1) Still no schematic.
2) No detail on what happens to switches when gear lever is pressed.
3) No account taken of switch bounce.
4) ...............
OK, you've found out how to drive the code button.
That's now revealed that you have not learned how to indent code to make it more readable.
Code is easier to trace if after each opening {, the following code is further indented 'til it meets the closing }.
It's still not easy to follow yours because you have to scroll.
Try to write each module/routine so that it is all viewable at once on the screen.
The whole thing is still too complex.
You have to learn how to debug code one section at a time.
Break the problem into small easy to manage sections.
Get each section to work on it's own.
Then put them together.
Have a look with a 'scope at what happens when you depress a switch.
You're PIC has a hardware UART. Use that to tell a PC what's going on.
You could try something like this:-
| Code: |
Main()
{
initialise(); // set up oscillator etc
while (1) // loop here forever
{
read_switches(); // sets new_switch_flag on a valid switch change
if (new_switch)
{
find_new_gear(); // work out new gear
display_gear(); // shows gear
}
delay_ms(1); // provides time-keeping
}
}
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Loop goes round roughly once per millisecond
Code read_switches(), reads switches and compares to state last time round.
With two switches, there are only four switch_states 0,1,2,3.
If state is same for a few ms in succession, then switch_state is valid (i.e. stopped bouncing).
If valid switch_state is different from previous one then sets new_switch_flag.
Code find_new_gear() uses switch_state and current gear to determine new gear, and reset new_switch_flag.
Display_gear turns ALL LEDs off, then lights ONE only.
Mike
EDIT I fear this project is going nowhere fast. |
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[email protected]
Joined: 23 Jun 2012
Posts: 22
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| Posted: Thu Dec 27, 2012 11:04 am |
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I think switch bouncing and delay is the problem in my code.
Is it possible by using analog inputs? |
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Mike Walne
Joined: 19 Feb 2004
Posts: 1785
Location: Boston Spa UK
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| Posted: Thu Dec 27, 2012 11:17 am |
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| [email protected] wrote: | I think switch bouncing and delay is the problem in my code.
Is it possible by using analog inputs? |
Of course it's possible to use analogue inputs.
A switch is essentially a digital device, so what makes you think that using the A2D will magically solve your problem?
I've already outlined how to deal with switch bounce.
A search on this forum will yield loads of other suggestions, code samples, explanations etc.
Where in your system do you think there is a delay issue?
Mike |
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temtronic
Joined: 01 Jul 2010
Posts: 9240
Location: Greensville,Ontario
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| Posted: Thu Dec 27, 2012 11:22 am |
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Of course you 'could' use analog inputs BUT that opens up a HUGE problem concerning analog 'noise' which can easily be worse than simple switch debounce noise!!!
Mike , and others have patiently provided you with a lot of valuable knowledge and tips on how to do this simple task.
Simply apply the 'words of wisdom' and build a simple 2 switches--PIC setup on your bench.Don't even think about trying on the '2wheeler'' until the bench setup works flawlessly.
Do more research either on the Web,PIC sites,the examples CCS supplies,etc. you're NOT the first one trying to get 2 switches to interface to a PIC.
hth
jay |
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