Merge branch 'master' into rcc-dev

Conflicts:
	Makefile

1 files changed, 145 insertions, 0 deletions

diff --git a/libmaple/timers.h b/libmaple/timers.h
new file mode 100644
index 0000000..18b0afb
--- /dev/null
+++ b/libmaple/timers.h
@@ -0,0 +1,145 @@
+/* *****************************************************************************
+ *  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
+