Hello,
I generally use a fairly tight loop with small delays and counters.
For the LEDs I use flash-pattern words.
I start at bit 0 of the flash-pattern word and, if it's a ONE, I turn the LED ON.
If it's a ZERO I turn the LED OFF.
Each time I pass through the loop I increment the flash-pattern word's bit counter by one and do the check again.
When the bit counter reaches 16 I reset it to 0 again (a word variable's bits are numbered 0 to 15).
Currently, I have a project with 5 switches and 5 LEDs.
Each LED has a flash-pattern word variable associated with it.
It works well, the flashing is smooth, and does not require interrupts.
If I want an LED to flash on and off quickly (50% duty-cycle), I load it's flash-pattern word variable with %0101010101010101. If I want the LED to flash on and off slowly (but also with a 50% duty-cycle), I load %0000000011111111. If I want it ON all of the time I load it with all ones. If I want it off all of the time I load the variable with all zeros. Basically, you have 65536 different flash-patterns to choose from and all you have to do is load one variable.
The beauty of this is that each LED "seems" to be operating independently with a mind of it's own. Other LEDs' flash-patterns are unaffected when one LED's pattern changes. Also, you can define flash-patterns for different modes as constants. This makes your code much more readable.
For instance...
Main:
If Button1 = 0 Then
LED1Pattern = OPERATING_MODE
Else
LED1Pattern = STANDBY_MODE
EndIf
Pause 10
Gosub UpdateLEDState
Goto Main
In the above example, "Button1" is the aliias for a switch input pin (active low). "Led1Pattern" is a word-sized variable the holds the flash pattern for LED #1. OPERATING_MODE and STANDYBY_MODE are 16-bit constants declared at the beginning of your program. And finally, "UpdateLEDState" is a subroutine (not shown above) that increments the flash-pattern bit-counter and then turns LED #1 on or off, depending on whether the current bit in "LED1Pattern" is a ONE or a ZERO. You could have as many LED flash-pattern words being "updated" in this routine as your RAM allows. I generally use arrays for my flash-patterns and then use a loop.
Anyway, have fun and welcome to PIC programming!
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