feat: pwm demo with timer

demo/pwm/pwm_2ch_complementary.c

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 /**
- * Demo: PWM 2-channel complementary output
+ * Demo: 2-channel complementary output
  * 
  * P1.0  -> 1k Ω resistor -> LED1+
  * P1.1  -> 1k Ω resistor -> LED2+

demo/pwm/pwm_2ch_timer2_interrupt.c

@@ -0,0 +1,91 @@
+// Copyright 2021 IOsetting <iosetting(at)outlook.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * Demo: 2-channel with timer2 interrupt
+ * 
+ * P1.0  -> 1k Ω resistor -> LED1+
+ * P1.1  -> 1k Ω resistor -> LED2+
+ * GND   -> LED1-
+ * GND   -> LED2-
+*/
+#include "fw_hal.h"
+
+__BIT dir = SET;
+uint8_t dc = 0;
+
+INTERRUPT(Timer2_Routine, EXTI_VectTimer2)
+{
+	PWMA_PWM1_SetCaptureCompareValue(dc);
+    UART1_TxHex(dc);
+    UART1_TxString("\r\n");
+    if (dir)
+    {
+        dc++;
+        if (dc == 0xFF) dir = !dir;
+    }
+    else
+    {
+        dc--;
+        if (dc == 0) dir = !dir;
+    }
+}
+
+void main(void)
+{
+    SYS_SetClock();
+    // UART1, baud 115200, baud source Timer1, 1T mode
+    UART1_ConfigMode1Dyn8bitUart(UART1_BaudSource_Timer1, HAL_State_ON, 115200);
+
+    // Set GPIO pins output mode
+    GPIO_P1_SetMode(GPIO_Pin_0|GPIO_Pin_1, GPIO_Mode_Output_PP);
+    // Turn off PWMA.1 before change its mode
+    PWMA_PWM1_SetPortState(HAL_State_OFF);
+    PWMA_PWM1N_SetPortState(HAL_State_OFF);
+    // Set PWMA.1 port direction output
+    PWMA_PWM1_SetPortDirection(PWMB_PortDirOut);
+    // Set PWMA.1 output low voltage when counter is less than target value
+    PWMA_PWM1_ConfigOutputMode(PWM_OutputMode_PWM_LowIfLess);
+    // Enable comparison value preload to make duty cycle changing smooth
+    PWMA_PWM1_SetComparePreload(HAL_State_ON);
+    // Turn on PWMA.1
+    PWMA_PWM1_SetPortState(HAL_State_ON);
+    // Turn on PWMA.1 complementary output
+    PWMA_PWM1N_SetPortState(HAL_State_ON);
+    // Set highest PWM clock
+    PWMA_SetPrescaler(0);
+    // PWM width = Period + 1 (side alignment), or AutoReloadPeriod * 2 (center alignment)
+    PWMA_SetPeriod(0xFF);
+    // Counter direction, down:from [PWMA_ARRH,PWMA_ARRL] to 0
+    PWMA_SetCounterDirection(PWM_CounterDirection_Down);
+    // Enable preload on reload-period
+    PWMA_SetAutoReloadPreload(HAL_State_ON);
+    // Enable output on PWMA.1P, PWMA.1N
+    PWMA_SetPinOutputState(PWM_Pin_1|PWM_Pin_1N, HAL_State_ON);
+    // Set PWMA.1 alternative ports to P1.0 and P1.1
+    PWMA_PWM1_SetPort(PWMA_PWM1_AlterPort_P10_P11);
+    // Enable overall output
+    PWMA_SetOverallState(HAL_State_ON);
+    // Start counter
+    PWMA_SetCounterState(HAL_State_ON);
+
+	// 1T mode, prescaler:255+1, frequency: 100
+	TIM_Timer2_Config(HAL_State_ON, 0xFF, 100);
+    // Timer2 interrupt: ON
+	EXTI_Timer2_SetIntState(HAL_State_ON);
+	EXTI_Global_SetIntState(HAL_State_ON);
+	TIM_Timer2_SetRunState(HAL_State_ON);
+
+    while(1);
+}

demo/tim/timer2_timer_1t.c

@@ -31,7 +31,6 @@ void main(void)
 	SYS_SetClock();
 	// UART1 configuration: baud 115200 with Timer1, 1T mode, no interrupt
     UART1_ConfigMode1Dyn8bitUart(UART1_BaudSource_Timer1, HAL_State_ON, 115200);
-	EXTI_Global_SetIntState(HAL_State_ON);
 	// 1T mode, prescaler:255+1, frequency: 5, interrupt: ON
 	TIM_Timer2_Config(HAL_State_ON, 0xFF, 5);
 	EXTI_Timer2_SetIntState(HAL_State_ON);