18F4431 Encoder input problem - Electronic Circuits Projects Diagrams Free

Andy_123 · 18th February 2007, 10:27 PM

Was playing with 18F4431 this cold weekend, few things still not clear:

- PWM mode works just fine, using 12 bits,
but if I am trying to read PTMRH - reading always 0, PTMRL - no problem - changing fast

- Encoder input - not working at all I just need aimple counter with A/B signals:
Here what I have:

Code:

 
  MOVLW B'11111111' 
  MOVWF TRISA, 0
  MOVLW B'00000100' 
  MOVWF QEICON, 0
  MOVLW B'11111111' 
  MOVWF MAXCNTL, 0
  MOVLW B'00000011' 
  MOVWF MAXCNTH, 0

Reading POSCNTH, POSCNTL - nothing always 0, if I write something to pos counter, I see these values

Any ideas?
Thanks

Andy_123 · 19th February 2007, 01:26 PM

Do I have to configure TMR5 if I don't need velocity mode?

Andy_123 · 20th February 2007, 01:48 AM

Answer is here, another error in the datasheet
http://forum.microchip.com/tm.aspx?m=201683

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18th February 2007, 10:27 PM	#1
Andy_123	18F4431 Encoder input problem Was playing with 18F4431 this cold weekend, few things still not clear: - PWM mode works just fine, using 12 bits, but if I am trying to read PTMRH - reading always 0, PTMRL - no problem - changing fast - Encoder input - not working at all I just need aimple counter with A/B signals: Here what I have: Code: MOVLW B'11111111' MOVWF TRISA, 0 MOVLW B'00000100' MOVWF QEICON, 0 MOVLW B'11111111' MOVWF MAXCNTL, 0 MOVLW B'00000011' MOVWF MAXCNTH, 0 Reading POSCNTH, POSCNTL - nothing always 0, if I write something to pos counter, I see these values Any ideas? Thanks

19th February 2007, 01:26 PM	#2
Andy_123	Do I have to configure TMR5 if I don't need velocity mode?

20th February 2007, 01:48 AM	#3
Andy_123	Answer is here, another error in the datasheet http://forum.microchip.com/tm.aspx?m=201683