add examples

RTL00_SDKV35a/example_sources/pwm/readme.txt

@@ -0,0 +1,13 @@
+Example Description
+
+This example describes how to use pwm
+
+Requirement Components:
+    1~4 LED
+
+Connect LED to below PWM pins and ground, then the LED would gradually become brighter and then darker with different speed.
+ - connect a LED to PC_0 and ground
+ - connect a LED to PC_1 and ground
+ - connect a LED to PC_2 and ground
+ - connect a LED to PC_3 and ground
+ 

RTL00_SDKV35a/example_sources/pwm/src/main.c

@@ -0,0 +1,94 @@
+/*
+ *  Routines to access hardware
+ *
+ *  Copyright (c) 2013 Realtek Semiconductor Corp.
+ *
+ *  This module is a confidential and proprietary property of RealTek and
+ *  possession or use of this module requires written permission of RealTek.
+ */
+
+#include "device.h"
+#include "pwmout_api.h"   // mbed
+#include "main.h"
+
+#define PWM_1       PC_0 
+#define PWM_2       PC_1 
+#define PWM_3       PC_2 
+#define PWM_4       PC_3 
+#define PWM_PERIOD  20000
+#define USE_FLOAT   0
+
+#if USE_FLOAT
+#define PWM_STEP    (1.0/20.0)
+float pwms[4]={0.0, 0.25, 0.5, 0.75};
+float steps[4]={PWM_STEP, PWM_STEP, PWM_STEP, PWM_STEP};
+#else
+#define PWM_STEP    (PWM_PERIOD/20)
+int pwms[4]={0, PWM_PERIOD/4, PWM_PERIOD/2, PWM_PERIOD/4*3};
+int steps[4]={PWM_STEP,PWM_STEP,PWM_STEP,PWM_STEP};
+#endif
+
+pwmout_t pwm_led[4];
+PinName  pwm_led_pin[4] =  {PWM_1, PWM_2, PWM_3, PWM_4};
+
+extern void RtlMsleepOS(u32 ms);
+
+void pwm_delay(void)
+{
+	for(int i=0;i<1000000;i++)
+		asm(" nop");
+}
+
+/**
+  * @brief  Main program.
+  * @param  None
+  * @retval None
+  */
+//int main_app(IN u16 argc, IN u8 *argv[])
+void main(void)
+{
+    int i;
+    
+    for (i=0; i<4; i++) {
+        pwmout_init(&pwm_led[i], pwm_led_pin[i]);
+        pwmout_period_us(&pwm_led[i], PWM_PERIOD);
+    }
+
+    while (1) {
+#if USE_FLOAT
+        for (i=0; i<4; i++) {
+            pwmout_write(&pwm_led[i], pwms[i]);
+
+            pwms[i] += steps[i];
+            if (pwms[i] >= 1.0) {
+                steps[i] = -PWM_STEP;
+                pwms[i] = 1.0;
+            }
+
+            if (pwms[i] <= 0.0) {
+                steps[i] = PWM_STEP;
+                pwms[i] = 0.0;
+            }
+        }
+#else        
+        for (i=0; i<4; i++) {
+            pwmout_pulsewidth_us(&pwm_led[i], pwms[i]);
+
+            pwms[i] += steps[i];
+            if (pwms[i] >= PWM_PERIOD) {
+                steps[i] = -PWM_STEP;
+                pwms[i] = PWM_PERIOD;
+            }
+
+            if (pwms[i] <= 0) {
+                steps[i] = PWM_STEP;
+                pwms[i] = 0;
+            }
+        }
+#endif        
+//        wait_ms(20);
+//        RtlMsleepOS(25);
+		pwm_delay();
+    }
+}
+