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/* *****************************************************************************
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Created: 12/18/09 02:38:10
* Copyright (c) 2009 Perry L. Hung. All rights reserved.
*
* ****************************************************************************/
/**
* @file timers.h
*
* @brief Timer prototypes and various definitions
*/
/* Note to self:
* The timer clock frequencies are automatically fixed by hardware.
* There are two cases:
* 1. if the APB prescaler is 1, the timer clock frequencies are
* set to the same frequency as that of the APB domain to which
* the timers are connected.
* 2. otherwise, they are set to twice (x2) the frequency of the
* APB domain to which the timers are connected.
* See stm32 manual, 77/995
*
* hence, 72 mhz timers
* */
/* Maple Timer channels:
* Timer Maple Pin STM32 Pin Type
* TIM1_CH1 D6 PA8 Advanced
* TIM1_CH2 D7 PA9 Advanced
* TIM1_CH3 D8 PA10 Advanced
*
* TIM2_CH1 D2 PA0
* TIM2_CH2 D3 PA1
* TIM2_CH3 D1 PA2
* TIM2_CH4 D0 PA3
*
* TIM3_CH1 D12 PA6
* TIM3_CH2 D11 PA7
* TIM3_CH3 EXT7 PB0
* TIM3_CH4 EXT8 PB1
*
* TIM4_CH1 EXT5 PB6
* TIM4_CH1 EXT9 PB7
* TIM4_CH1 EXT15 PB8
* TIM4_CH1 EXT4 PB9
*
* Not supported:
* TIM1_CH4 USBDM, not available PA11 Advanced
* TIM1_CH1_N EXT12 PB13
* TIM1_CH2_N EXT13 PB14
* TIM1_CH3_N EXT14 PB15
* */
/* I don't like the Arduino API for dealing with pin modes.
* How about...
*
* pinMode(digitalPin, PWM);
* pwmWrite(digitalPin) */
#ifndef _TIMERS_H_
#define _TIMERS_H_
#include <inttypes.h>
#ifdef __cplusplus
extern "C"{
#endif
typedef volatile uint32_t* TimerCCR;
#define TIMER1_BASE 0x40012C00
#define TIMER2_BASE 0x40000000
#define TIMER3_BASE 0x40000400
#define TIMER4_BASE 0x40000800
#define ARPE BIT(7) // Auto-reload preload enable
#define NOT_A_TIMER 0
#define TIMER1_CH1_CCR (TimerCCR)(TIMER1_BASE + 0x34)
#define TIMER1_CH2_CCR (TimerCCR)(TIMER1_BASE + 0x38)
#define TIMER1_CH3_CCR (TimerCCR)(TIMER1_BASE + 0x3C)
#define TIMER1_CH4_CCR (TimerCCR)(TIMER1_BASE + 0x40)
#define TIMER2_CH1_CCR (TimerCCR)(TIMER2_BASE + 0x34)
#define TIMER2_CH2_CCR (TimerCCR)(TIMER2_BASE + 0x38)
#define TIMER2_CH3_CCR (TimerCCR)(TIMER2_BASE + 0x3C)
#define TIMER2_CH4_CCR (TimerCCR)(TIMER2_BASE + 0x40)
#define TIMER3_CH1_CCR (TimerCCR)(TIMER3_BASE + 0x34)
#define TIMER3_CH2_CCR (TimerCCR)(TIMER3_BASE + 0x38)
#define TIMER3_CH3_CCR (TimerCCR)(TIMER3_BASE + 0x3C)
#define TIMER3_CH4_CCR (TimerCCR)(TIMER3_BASE + 0x40)
#define TIMER4_CH1_CCR (TimerCCR)(TIMER4_BASE + 0x34)
#define TIMER4_CH2_CCR (TimerCCR)(TIMER4_BASE + 0x38)
#define TIMER4_CH3_CCR (TimerCCR)(TIMER4_BASE + 0x3C)
#define TIMER4_CH4_CCR (TimerCCR)(TIMER4_BASE + 0x40)
/* Turn on timer with prescale as the divisor
* void timer_init(uint32_t timer, uint16_t prescale)
* timer -> {1-4}
* prescale -> {1-65535}
* */
void timer_init(uint8_t, uint16_t);
void timers_disable(void);
void timers_disable_channel(uint8, uint8);
/* Turn on PWM with duty_cycle on the specified channel in timer.
* This function takes in a pointer to the corresponding CCR
* register for the pin cause it saves pwmWrite() a couple of
* cycles.
*
* void timer_pwm(uint8_t channel, uint8_t duty_cycle);
* channel -> {TIMERx_CHn_CCR}
* duty_cycle -> {0-65535}
*
* PRECONDITIONS:
* pin has been set to alternate function output
* timer has been initialized
*/
static inline void timer_pwm_write_ccr(TimerCCR CCR, uint16_t duty_cycle) {
*CCR = duty_cycle;
}
#ifdef __cplusplus
} // extern "C"
#endif
#endif
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