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Anything in C?
--- In , "Patrick Reitelbach" <preitelbach@y...> wrote: > It can be found at www.polydevelopment.com/pd_code/servo. > my_servo_2_channel.asm. > > pr > --- In , honamos@y... wrote: > > This is indeed for RC Servo Control. Do you think you could pass > > along that code? > > > > Thanks, > > Shamoon > > > > --- In , "Patrick Reitelbach" > > <preitelbach@y...> wrote: > > > I do not think you will be able to get the numbers you want with > a > > > standard timer setup. The PWM cannot get that slow with a 8Mhz > > > clock. I made a 60Hz source with a 16F628 using its internal > > 37Khz > > > clock. > > > > > > Maybe you could setup a timer/interrupt for your required control > > > step value (how fine of control do you want?) and count the > > > interrupts in an isr to control your output(s). Like 100us > > > resolution gives 12 steps between 600 and 1800us. Set a timer to > > > overflow every 100us and do the counting. > > > > > > Is this by chance to be used for RC servo control? > > > > > > I have an assembly program for the 628 which controls 2 servos at > > > 4Mhz clock. With 8 Mhz you could control 4. I process all servo > > > outputs in parallel vs serially (one at a time). The serial > > methods > > > I looked at were cpu time hogs. This means for 2 ms about 90% of > > cpu > > > cycles are used for servo control. Other tasks have the cpu 100% > > for > > > the remaining 18 ms. > > > > > > pr > > > --- In , honamos@y... wrote: > > > > Nope, this is just one of the various things. The clock speed > I > > > > have is 8Mhz. > > > > > > > > --- In , "Patrick Reitelbach" > > > > <preitelbach@y...> wrote: > > > > > Is this the only thing the pic will be doing? What is the > > clock > > > > > speed you want to use? > > > > > pr > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > That's about right, yeah... Ideas? > > > > > > > > > > > > Shamoon > > > > > > > > > > > > --- In , "Patrick Reitelbach" > > > > > > <preitelbach@y...> wrote: > > > > > > > You want a pulse every 20ms and control the pulse width > > from > > > > > 600us > > > > > > to > > > > > > > 1800us. Is this correct? > > > > > > > > > > > > > > pr > > > > > > > --- In , honamos@y... wrote: > > > > > > > > Any ideas? > > > > > > > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > > Hey now, > > > > > > > > > I have the PIC18F458 and I'm using the CCS C > > compiler. > > > My > > > > > > > > question > > > > > > > > > is simple. I want to output a square wave at 50Hz > and > > > > vary > > > > > > the > > > > > > > > duty > > > > > > > > > cycle between 3% and 9%. Any ideas how to accomplish > > > > this? > > > > > I > > > > > > > > know > > > > > > > > > I should use "SETUP_TIMER", I'm just not sure how. > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > Shamoon |
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CCP PWM
Started by ●July 7, 2004
Reply by ●July 9, 20042004-07-09
Reply by ●July 12, 20042004-07-12
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Any ideas?
> --- In , "Patrick Reitelbach" > <preitelbach@y...> wrote: > > It can be found at www.polydevelopment.com/pd_code/servo. > > my_servo_2_channel.asm. > > > > pr > > --- In , honamos@y... wrote: > > > This is indeed for RC Servo Control. Do you think you could > pass > > > along that code? > > > > > > Thanks, > > > Shamoon > > > > > > --- In , "Patrick Reitelbach" > > > <preitelbach@y...> wrote: > > > > I do not think you will be able to get the numbers you want > with > > a > > > > standard timer setup. The PWM cannot get that slow with a > 8Mhz > > > > clock. I made a 60Hz source with a 16F628 using its internal > > > 37Khz > > > > clock. > > > > > > > > Maybe you could setup a timer/interrupt for your required > control > > > > step value (how fine of control do you want?) and count the > > > > interrupts in an isr to control your output(s). Like 100us > > > > resolution gives 12 steps between 600 and 1800us. Set a timer > to > > > > overflow every 100us and do the counting. > > > > > > > > Is this by chance to be used for RC servo control? > > > > > > > > I have an assembly program for the 628 which controls 2 servos > at > > > > 4Mhz clock. With 8 Mhz you could control 4. I process all > servo > > > > outputs in parallel vs serially (one at a time). The serial > > > methods > > > > I looked at were cpu time hogs. This means for 2 ms about 90% > of > > > cpu > > > > cycles are used for servo control. Other tasks have the cpu > 100% > > > for > > > > the remaining 18 ms. > > > > > > > > pr > > > > --- In , honamos@y... wrote: > > > > > Nope, this is just one of the various things. The clock > speed > > I > > > > > have is 8Mhz. > > > > > > > > > > --- In , "Patrick Reitelbach" > > > > > <preitelbach@y...> wrote: > > > > > > Is this the only thing the pic will be doing? What is the > > > clock > > > > > > speed you want to use? > > > > > > pr > > > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > That's about right, yeah... Ideas? > > > > > > > > > > > > > > Shamoon > > > > > > > > > > > > > > --- In , "Patrick Reitelbach" > > > > > > > <preitelbach@y...> wrote: > > > > > > > > You want a pulse every 20ms and control the pulse > width > > > from > > > > > > 600us > > > > > > > to > > > > > > > > 1800us. Is this correct? > > > > > > > > > > > > > > > > pr > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > > Any ideas? > > > > > > > > > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > > > Hey now, > > > > > > > > > > I have the PIC18F458 and I'm using the CCS C > > > compiler. > > > > My > > > > > > > > > question > > > > > > > > > > is simple. I want to output a square wave at 50Hz > > and > > > > > vary > > > > > > > the > > > > > > > > > duty > > > > > > > > > > cycle between 3% and 9%. Any ideas how to > accomplish > > > > > this? > > > > > > I > > > > > > > > > know > > > > > > > > > > I should use "SETUP_TIMER", I'm just not sure how. > > > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > > Shamoon |
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Reply by ●July 13, 20042004-07-13
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piclist.com has some C examples. join the MiniSumoMarkIII group and look in the message base (#3440) and the files. examples there. --- In , honamos@y... wrote: > Any ideas? > > --- In , "Patrick Reitelbach" > > <preitelbach@y...> wrote: > > > It can be found at www.polydevelopment.com/pd_code/servo. > > > my_servo_2_channel.asm. > > > > > > pr > > > --- In , honamos@y... wrote: > > > > This is indeed for RC Servo Control. Do you think you could > > pass > > > > along that code? > > > > > > > > Thanks, > > > > Shamoon > > > > > > > > --- In , "Patrick Reitelbach" > > > > <preitelbach@y...> wrote: > > > > > I do not think you will be able to get the numbers you want > > with > > > a > > > > > standard timer setup. The PWM cannot get that slow with a > > 8Mhz > > > > > clock. I made a 60Hz source with a 16F628 using its > internal > > > > 37Khz > > > > > clock. > > > > > > > > > > Maybe you could setup a timer/interrupt for your required > > control > > > > > step value (how fine of control do you want?) and count the > > > > > interrupts in an isr to control your output(s). Like 100us > > > > > resolution gives 12 steps between 600 and 1800us. Set a > timer > > to > > > > > overflow every 100us and do the counting. > > > > > > > > > > Is this by chance to be used for RC servo control? > > > > > > > > > > I have an assembly program for the 628 which controls 2 > servos > > at > > > > > 4Mhz clock. With 8 Mhz you could control 4. I process all > > servo > > > > > outputs in parallel vs serially (one at a time). The serial > > > > methods > > > > > I looked at were cpu time hogs. This means for 2 ms about > 90% > > of > > > > cpu > > > > > cycles are used for servo control. Other tasks have the cpu > > 100% > > > > for > > > > > the remaining 18 ms. > > > > > > > > > > pr > > > > > --- In , honamos@y... wrote: > > > > > > Nope, this is just one of the various things. The clock > > speed > > > I > > > > > > have is 8Mhz. > > > > > > > > > > > > --- In , "Patrick Reitelbach" > > > > > > <preitelbach@y...> wrote: > > > > > > > Is this the only thing the pic will be doing? What is > the > > > > clock > > > > > > > speed you want to use? > > > > > > > pr > > > > > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > That's about right, yeah... Ideas? > > > > > > > > > > > > > > > > Shamoon > > > > > > > > > > > > > > > > --- In , "Patrick Reitelbach" > > > > > > > > <preitelbach@y...> wrote: > > > > > > > > > You want a pulse every 20ms and control the pulse > > width > > > > from > > > > > > > 600us > > > > > > > > to > > > > > > > > > 1800us. Is this correct? > > > > > > > > > > > > > > > > > > pr > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > > > Any ideas? > > > > > > > > > > > > > > > > > > > > --- In , honamos@y... wrote: > > > > > > > > > > > Hey now, > > > > > > > > > > > I have the PIC18F458 and I'm using the CCS C > > > > compiler. > > > > > My > > > > > > > > > > question > > > > > > > > > > > is simple. I want to output a square wave at > 50Hz > > > and > > > > > > vary > > > > > > > > the > > > > > > > > > > duty > > > > > > > > > > > cycle between 3% and 9%. Any ideas how to > > accomplish > > > > > > this? > > > > > > > I > > > > > > > > > > know > > > > > > > > > > > I should use "SETUP_TIMER", I'm just not sure > how. > > > > > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > Shamoon |
