In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Matthias09 wrote:

Bean, 

thanks for the idea. I will implement it. I am curious: what are the advantages to use two pins? so far I see the following ones:

- shorter interrupt routine, less interrupts are skipped therefore
- due to I now have two pins detecting the signal in different ports, that are alternating interrupting the program, the second interrupt is put into waitlist, when the first one is processed, rather than just ignored

and: the problem with the rising/falling edge detection I had initially started this topic for solved itself with a new coding of the program. It was just a software bug. For all who are interested: this is the working encoder routine:

[code]
ISR_Start:

 WKPND_B = int_storage
 

 IF int_storage = %0001 THEN 			'Channel A Interrupt: count only, if A alone fires (other possible combinations: 0010: index fires, 0011: index + A fires)
	
	IF edge = 1 THEN			'change edge detection mode with every interrupt of A, no matter of B
		WKED_B  = %11111111 		'alter edge detection to falling edge on A
		edge = 0			'change edge detection mode variable to 0 for next interrupt
	ELSE
 		WKED_B  = %00000000 		'alter edge detection to rising edge on A
		edge = 1			'change edge detection mode variable to 1 for next interrupt
	ENDIF


	IF signal_B = 1 THEN 			'count only, if B is high

		IF edge = 1 THEN 		'check the current edge detection mode, here: rising edge

			angle = angle + 1 	'increment   ??? recheck how to count
		
			toggle led3
		
		ELSE
			angle = angle - 1 	'decrement   ??? recheck how to count
		
			toggle led4
			
		ENDIF

	ENDIF

ELSE						'Index Channel Interrupt. if index fires (no mater if A also fires), then reset angle to 90 deg.

	WKEN_B  = %11111100			'enable channel A interrupt (actually only has to be done after the first fire (as A is initally disabled). 
						'but to a routine would slow the process, which is not good.
	angle = 90				'reset angle
	Toggle Led2				'show that

ENDIF


 ISR_Exit:
 WKPND_B = %00000000 				'clear pending register, ALL bits

 RETURNINT 					'end of interrupt handler
[/code]


Matthias

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