PWM stops after short time - Raspberry Pi Forums

hi guys,

reason can't pwm function... have no idea why it's switch on correctly after 'sleep' on it's automatically shuts off. can't seem find in code suggesting pwm.stop() command...

i'm trying in 'up' statement setting count '1' , thereby disabling next time if class activate pwm signal again due continuous pressing of button. count stored in __init__ statement make sure kept when class exited.

i've added print 'pause' statement check if possibly count reset 0 else statement. see no print of statement guess problem should not here.

can me solve problem? or there possibly better solution model this?

thanx in advance!

code:

code: select all

import cwiid, time #wii module, time module import rpi.gpio gpio   #the gpio module  class states:     def __init__(self):         #first disable ports when creating class         gpio.output(4,false) #ena         gpio.output(27,false) #in1 (forward)         gpio.output(22,false) #in2 (backward)         gpio.output(23,false) #in3 (forward)         gpio.output(24,false) #in4 (backward)         gpio.output(5,false) #enb         self.count = 0              def press(self,state):         #now following controlling motors         if state == 'up' , self.count != 1:             gpio.output(4,true) #ena             gpio.output(27,false) #in1             gpio.output(22,true) #in2             gpio.output(23,false) #in3             gpio.output(24,true) #in4             gpio.output(5,true) #enb             time.sleep(.5)             p2=gpio.pwm(22,50)             p3=gpio.pwm(24,50)             print 'pwm activated'             time.sleep(.5)             p2.start(75)             p3.start(75)             print 'pwm started'             self.count = 1          else:             #do following when no buttons pressed:             try:                 p1.stop()             except unboundlocalerror:                 print 'unbound error 1'             try:                 p2.stop()             except unboundlocalerror:                 print 'unbound error 2'             try:                 p3.stop()             except unboundlocalerror:                 print 'unbound error 3'             try:                 p4.stop()             except unboundlocalerror:                 print 'unbound error 4'             print 'pause'             gpio.output(4,false) #ena             gpio.output(27,false) #in1             gpio.output(22,false) #in2             gpio.output(23,false) #in3             gpio.output(24,false) #in4             gpio.output(5,false) #enb             self.count = 0                      print 'class exited'              def main():     print 'initializing...'     time.sleep(1)          #create instances use on board , set output     print 'mapping gpio ports...'     gpio.setwarnings(false) #disable warnings     gpio.setmode(gpio.bcm) #use bcm board layout (gpio numbering)     gpio.setup(4,gpio.out) #engine on     gpio.setup(5,gpio.out) #engine b on     gpio.setup(27,gpio.out) #in1 (forward engine a)     gpio.setup(22,gpio.out) #in2 (backward engine a)     gpio.setup(23,gpio.out) #in3 (forward engine b)     gpio.setup(24,gpio.out) #in4 (backward engine b)     time.sleep(2)          #create connection wii mote     wiimote=cwiid.wiimote() #connects wii     print 'connected'              #now make sure wii remote reports pressed buttons     wiimote.rpt_mode = cwiid.rpt_btn          #create class     button=states()          while wiimote.state['buttons'] != 128:         if wiimote.state['buttons'] == 512:             button.press('up')                 else:             button.press('pause')          print 'closing ports'     gpio.output(4,false) #ena     gpio.output(27,false) #in1     gpio.output(22,false) #in2     gpio.output(23,false) #in3     gpio.output(24,false) #in4     gpio.output(5,false) #enb          gpio.cleanup()      main() 

i didn't if using frequent pwm starts , stops stop doing so. try setting dutycycle 0 rather doing stop/start.

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