142 lines
4.3 KiB
C++
142 lines
4.3 KiB
C++
// PWM Driver - LPC176x - Single edge only, does not support double edge PWM
|
|
//
|
|
// Copyright 2017 Brett Fleming
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
// of this software and associated documentation files (the "Software"), to deal
|
|
// in the Software without restriction, including without limitation the rights
|
|
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
// copies of the Software, and to permit persons to whom the Software is
|
|
// furnished to do so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in
|
|
// all copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
// IN THE SOFTWARE.
|
|
|
|
#include "pwm_driver.h"
|
|
#include "LPC17xx.h"
|
|
|
|
#include "grbl.h"
|
|
|
|
//LPC_PWM1_BASE
|
|
//LPC_PWM1 is of type LPC_PWM_TypeDef at Address LPC_PWM1_BASE
|
|
|
|
/*
|
|
Theory of operation: Initialize, start running, change width any time while running.
|
|
|
|
pwm_init(PWM1_CH1, 1000, 0);
|
|
pwm_enable(PWM1_CH1);
|
|
pwm_set_width(250);
|
|
sleep(1)
|
|
pwm_set_width(500);
|
|
sleep(1)
|
|
pwm_set_width(999);
|
|
sleep(1)
|
|
pwm_disable(PWM1_CH1);
|
|
*/
|
|
|
|
|
|
const PWM_Channel_Config PWM1_CH1 = {
|
|
&(LPC_PWM1->MR1), //Match Register
|
|
(1 << 9), //PWM Enable
|
|
(1 << 1) //Latch Enable Register
|
|
};
|
|
|
|
const PWM_Channel_Config PWM1_CH2 = {
|
|
&(LPC_PWM1->MR2), //Match Register
|
|
(1 << 10), //PWM Enable
|
|
(1 << 2) //Latch Enable Register
|
|
};
|
|
|
|
const PWM_Channel_Config PWM1_CH3 = {
|
|
&(LPC_PWM1->MR3), //Match Register
|
|
(1 << 11), //PWM Enable
|
|
(1 << 3) //Latch Enable Register
|
|
};
|
|
|
|
const PWM_Channel_Config PWM1_CH4 = {
|
|
&(LPC_PWM1->MR4), //Match Register
|
|
(1 << 12), //PWM Enable
|
|
(1 << 4) //Latch Enable Register
|
|
};
|
|
|
|
const PWM_Channel_Config PWM1_CH5 = {
|
|
&(LPC_PWM1->MR5), //Match Register
|
|
(1 << 13), //PWM Enable
|
|
(1 << 5) //Latch Enable Register
|
|
};
|
|
|
|
const PWM_Channel_Config PWM1_CH6 = {
|
|
&(LPC_PWM1->MR6), //Match Register
|
|
(1 << 14), //PWM Enable
|
|
(1 << 6) //Latch Enable Register
|
|
};
|
|
|
|
|
|
|
|
|
|
//Smoothie board uses P2.4 and P2.5 as PWM outputs
|
|
|
|
//UM10360 LPC17xx Chapter 24 - Pulse Width Modulation
|
|
|
|
//
|
|
// channel - Which of the 6 PWM channels to init.
|
|
// period - what is the overall period, in PCLK cycles, for ALL PWMs (not just the provided one)
|
|
//
|
|
void pwm_init(PWM_Channel_Config* channel, uint32_t period, uint32_t width) {
|
|
//Power up PCONP
|
|
|
|
//Match Control - Continous operation (no interrupts, no timer reset)
|
|
LPC_PWM1->MCR = 0x0000;
|
|
|
|
//PWM Control Register - Single Edge (0 for bits 2-6) mode for all PWMs
|
|
LPC_PWM1->PCR &= 0xFF00;
|
|
|
|
//PWM Control Register - Disable output for channel
|
|
LPC_PWM1->PCR &= ~channel->PCR_Enable_Mask;
|
|
|
|
//Disable Capture
|
|
LPC_PWM1->CCR = 0x0000;
|
|
|
|
//PWM Timer Control Register - Counter Enable, PWM Enable
|
|
LPC_PWM1->TCR = (1 << 0) | (1 << 3);
|
|
|
|
//PWM Counter Control Register - Use Timer Mode (Counter Mode is for external clocks, not PWM)
|
|
LPC_PWM1->CTCR = 0x0000;
|
|
|
|
pwm_set_period(period);
|
|
pwm_set_width(channel, width);
|
|
}
|
|
|
|
void pwm_set_period(uint32_t period) {
|
|
LPC_PWM1->MR0 = period;
|
|
|
|
//If we are running, this will make the MRx register on the next cycle
|
|
LPC_PWM1->LER = (1 << 0);
|
|
}
|
|
|
|
void pwm_set_width(PWM_Channel_Config* channel, uint32_t width) {
|
|
*(channel->MRn) = width;
|
|
|
|
//If we are running, this will make the MRx register on the next cycle
|
|
LPC_PWM1->LER |= channel->LER_Enable_Mask;
|
|
}
|
|
|
|
void pwm_enable(PWM_Channel_Config* channel) {
|
|
//PWM Control Register - Enable output for channel
|
|
LPC_PWM1->PCR |= channel->PCR_Enable_Mask;
|
|
}
|
|
|
|
void pwm_disable(PWM_Channel_Config* channel) {
|
|
//PWM Control Register - Disable output for channel
|
|
LPC_PWM1->PCR &= ~channel->PCR_Enable_Mask;
|
|
}
|
|
|