Originally Posted by
dan gill
Ok guys,
I've tried the reset deal and the comparison deal. I'm driving an R/C servo, so I can't use any other pause other than the 50Hz update pause. I need the tmr1L to do everything in the background without upsetting the servo refresh rate. I used the COUNT command and it would work the best for what I'm doing if it didn't require such a long pause for the count. I spoke with Charles at MELABS and suggested the tmr1 use. Here's a snippet of the program code. I can't use the tmr0 either. I need the pinout. There is no room to use a larger chip either.
Chip is a 16F690
PROGRAMSET:
SEROUT LCD,R,[I,LINE4]
SEROUT LCD,R,["PROGRAMSET"]
A=0
high LED4 'TURN ON GREEN LED TO SHOW SYSTEM READY
FOR A= 1 TO 50 '1 SECOND TIME LOOP COUNTER FOR TMR1L
IF A=50 THEN GROUNDSPEED 'LOOP FOR CHECKING GROUNDSPEED
IF SW1=1 AND SW2=1 THEN RESET 'push switch 1 first
HIGH SERVO
PAUSEUS (1000+S)
LOW SERVO
PAUSE 16
NEXT A
GOTO PROGRAMSET
GROUNDSPEED: 'CHECKS GROUNDSPEED EVERY 1 SECOND
SEROUT LCD,R,[I,1]
SEROUT LCD,R,[I,LINE1]
SEROUT LCD,R,["GROUNDSPEED"]
SEROUT LCD,R,[I,LINE2]
SEROUT LCD,R,["TMR1L=",#TMR1L]
IF TMR1L>60 THEN TIMERRESET 'TMR1L RESETS IF SPEED GREATER THAN 60
HIGH SERVO
PAUSEUS (1000+S)
LOW SERVO
PAUSE 16
My program works wonderfully if I could just get the last of the code to work.
Do you guys think I could use a smaller reset and check it like Henrik has suggested. The only problem I can see with the method is what if the program happens to check the timer when it's resetting? That would give a false reading. The absolute bottom line is I must be positive of when the shaft is no longer rotating, or at the very least, moving very slowly. Once the shaft stops moving, I can tell the servo to move, but not before. I really am upset that I have over 3000 words of code and that I can't figure out what is probably only a few words to complete the program.
I really appreciate all the help. Thanks.
Dan
Missing code
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