add examples

RTL00_SDKV35a/example_sources/uart_clock/readme.txt

@@ -0,0 +1,16 @@
+Example Description
+
+This example describes how to use UART TX to simulate clock source
+
+Required Components:
+    Oscilloscope
+
+Connect to PC
+ - Connect Ground: connect to GND of oscilloscope
+ - Use UART1
+	GPIOA_6 as UART1_RX connect NOTHING
+	GPIOA_7 as UART1_TX connect to probe of oscilloscope
+
+
+This example shows: 
+1. Clock signal output from UART1_TX to oscilloscope

RTL00_SDKV35a/example_sources/uart_clock/src/main.c

@@ -0,0 +1,94 @@
+/*
+ *  Routines to access hardware
+ *
+ *  Copyright (c) 2015 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 "serial_api.h"
+#include "serial_ex_api.h"
+#include "main.h"
+
+#define UART_TX    PA_7    
+#define UART_RX    PA_6    
+
+/* 100 bytes data, 500 clocks, provide buadrate/2 frequency */
+#define SREAM_LEN 128
+char sim_clock[SREAM_LEN+1];
+
+
+volatile uint32_t is_stop = 0;
+static serial_t    sobj_clk;
+
+void uart_clock_send_string(serial_t *sobj, char *pstr)
+{
+    int32_t ret=0;
+
+    ret = serial_send_stream_dma(sobj, pstr, _strlen(pstr));
+    if (ret != 0) {
+        DBG_8195A("%s Error(%d)\n", __FUNCTION__, ret);        
+    }
+}
+
+void uart_clock_send_string_done(uint32_t id)
+{
+    serial_t    *sobj = (void*)id;
+	if(!is_stop)
+		uart_clock_send_string(sobj, sim_clock);
+}
+
+void uart_clock_deinit(void)
+{
+	is_stop = 1;
+	serial_free(&sobj_clk);
+}
+
+void uart_clock_init(int rate)
+{
+    //serial_t    sobj;
+    int ret;
+    int i;
+
+    for (i=0;i<SREAM_LEN;i++) {
+        sim_clock[i] = 0x55;
+    }
+    sim_clock[i] = 0;
+    
+    serial_init(&sobj_clk,UART_TX,UART_RX);
+	serial_baud(&sobj_clk, rate*2);
+    
+    serial_format(&sobj_clk, 8, ParityNone, 0);
+
+    serial_send_comp_handler(&sobj_clk, (void*)uart_clock_send_string_done, (uint32_t) &sobj_clk);
+}
+
+void uart_clock_on(void)
+{
+	is_stop = 0;
+	uart_clock_send_string(&sobj_clk, sim_clock);
+}
+
+void uart_clock_off(void)
+{
+	is_stop = 1;
+    serial_send_stream_abort(&sobj_clk);
+}
+
+void main(void)
+{
+	// only support 33kHz, 36kHz, 36.7kHz 38kHz, 40kHz, 56kHz
+	uart_clock_init(38000);
+	
+	while(1) {
+        uart_clock_on();
+        wait_ms(5000);
+        uart_clock_off();
+        wait_ms(5000);        
+    }
+
+}
+
+