Hi guys,
first of all I am new to RP please help me out here. (https://learn.adafruit.com/adafruit-16- ... spberry-pi)
I am using this i2c servo driver for my project. how can i get a digital signal using pwm (ON/OFF)? because i ve 2 dc motors and 5 servos to control. i want use 4 pwm channels(basically how to get a digital output from this channels ) to control 2 motors that attached to l 298d. please help me out here.
thanks
Adafruit 16 Channel Servo Driver with Raspberry Pi
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Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
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- adafruit_support_bill
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
The "setPWM" function specifies an ON time and an OFF time. These are numbers between 0 and 4095 representing increments in PWM cycle.
To turn an output OFF, set both ON and OFF times to 0.
To turn it ON, set the ON time to 0 and the OFF time to 4095.
https://learn.adafruit.com/adafruit-16- ... -reference
To turn an output OFF, set both ON and OFF times to 0.
To turn it ON, set the ON time to 0 and the OFF time to 4095.
https://learn.adafruit.com/adafruit-16- ... -reference
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
Thanks bill,
but i tried that already. it doesnt work. i even checked the voltage levels. they are 0V.but when i attached a servo its working just fine
but i tried that already. it doesnt work. i even checked the voltage levels. they are 0V.but when i attached a servo its working just fine
- adafruit_support_bill
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
Hmmm. Looking at the datasheet, to set the output HIGH, it should be ON = 4096 and OFF = 0.
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
thanks anyway i ll try more.
- adafruit_support_bill
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
Look carefully. That is different from what I suggested in my earlier response. I just tested and this works on the Arduino version of the library.it should be ON = 4096 and OFF = 0.
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Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
i did this modification to example..
pwm.setPWM(0,0,4096)
pwm.setPWM(1,0,0)
pwm.setPWM(2,0,4096)
pwm.setPWM(3,0,0)
i want the out put in the board to be channel 0 => 5v ,ch 1=> 0v and go on...is it possible with this board?
pwm.setPWM(0,0,4096)
pwm.setPWM(1,0,0)
pwm.setPWM(2,0,4096)
pwm.setPWM(3,0,0)
i want the out put in the board to be channel 0 => 5v ,ch 1=> 0v and go on...is it possible with this board?
- adafruit_support_bill
- Posts: 88093
- Joined: Sat Feb 07, 2009 10:11 am
Re: Adafruit 16 Channel Servo Driver with Raspberry Pi
That is backwards. On (4096) comes before Off (0)
https://learn.adafruit.com/adafruit-16- ... -reference
https://learn.adafruit.com/adafruit-16- ... -reference
setPWM(self, channel, on, off)
Description
This function sets the start (on) and end (off) of the high segment of the PWM pulse on a specific channel. You specify the 'tick' value between 0..4095 when the signal will turn on, and when it will turn of. Channel indicates which of the 16 PWM outputs should be updated with the new values.
Arguments
channel: The channel that should be updated with the new values (0..15)
on: The tick (between 0..4095) when the signal should transition from low to high
off:the tick (between 0..4095) when the signal should transition from high to low
Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/