Diff: main.cpp

Revision:

0:3355c5b6d8fd

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Jul 24 10:37:58 2020 +0000
@@ -0,0 +1,128 @@
+//UART FLUSH()
+
+// This program is further improvement of circular buffer concepts
+/* Note : In Serial class library /or RawSerial class library there is no flush() command.
+Sometimes buffer clearing process require when you want to compare receiving data with pre-stored value
+or when doing some string related operation, because if you not clear UART buffer you will get old stored data.
+*/
+
+/*Note : simple way to clear Buffer : Read it , & reset all UART process related counter.*/
+
+//PROGRAM SUBJECT : UART BUFFER CLEAR / FLUSH()
+//Date : 24 July 2020 Version 1.0
+//JAYDEEP SHAH -- radhey04ec@gmail.com
+
+// I am sending one by one characters to slave and slave provide response according it , Ex : 'T' = Test Mode
+
+#include "mbed.h"
+#define BUFFER_SIZE 90   //SIZE OF BUFFER   ---DEPENDS ON YOUR DATA SIZE  --This is circular buffer
+
+char rxBuffer[BUFFER_SIZE];  //CREATE CIRCULAR BUFFER  -- TO STORE RECEIVE DATA
+
+unsigned int bufferReadingIndex=0;  //CREATE POINTER TO READ DATA FROM UART AND STORE INTO ARRAY
+
+unsigned int i=0; //counter to read data from buffer Array
+
+// 0 - Rx - PA_0   : Board Tx ___ Arduino Connector socket >>> First_pin _Orange  -- If FTDI CABLE USE
+// 1 - Tx - PA_1   : Board Rx ____ Arduino connector socket  >>> Second_pin _red  -- If FTDI CABLE USE
+
+//If you use only Serial calss , there is chance of damage OS because of MUTEX GUARD
+
+//use RawSerial class
+RawSerial UT(PA_0,PA_1);  //UART PIN DECLARATION
+RawSerial pc(USBTX,USBRX);  //HOST PC TERMINAL  - 9600 BAUD WITH 8-N-1 STTING
+
+//NOTE : UT OBJ FOR SLAVE BOARD & pc OBJ FOR TERMINAL
+
+//DEFINE Rx Interrupt function --DECLARATION
+void RxInterrupt(void);
+
+//Function that read response data
+void response(void);
+
+//FLUSH() UART
+
+void FLUSH(void); //Function declaration only
+
+int main()
+{
+UT.baud(57600);  //BAUD RATE SETTING
+UT.format(8,Serial::None,1);   //FORMAT OF UART COMMUNICATION
+
+//INTERRUPT ATTACHMENT WHEN RECEIVE DATA
+UT.attach(&RxInterrupt,Serial::RxIrq);
+
+pc.printf("\n TESTING TURN ON : \n");
+wait(1);
+
+UT.putc('T');  //ENTER IN TEST MODE  -- SLAVE BOARD ENTER INTO TEST MODE
+wait(0.5);
+response();  //Read Response from Slave 
+FLUSH(); // BEFORE SENDING /RECEIVING NEW DATA
+
+ThisThread::sleep_for(1000);
+
+UT.putc('d');   // RED LED OF SLAVE BOARD ON
+wait(1);
+response(); //Read Response from Slave
+FLUSH(); // BEFORE SENDING /RECEIVING NEW DATA
+ThisThread::sleep_for(5000);
+
+
+UT.putc('b');  // RED LED OF SLAVE BOARD OFF
+wait(1);
+response();  //Read Response from slave
+FLUSH(); // BEFORE SENDING /RECEIVING NEW DATA
+ThisThread::sleep_for(1000);
+
+UT.putc('Q');  //QUIT FROM TEST MODE -- NORMAL MODE SELECT
+wait(1);
+response();//Read response from Slave
+FLUSH(); // BEFORE SENDING /RECEIVING NEW DATA
+ThisThread::sleep_for(3000);
+
+while(1)
+{
+}
+
+}
+
+
+void RxInterrupt()      //if Rx buffer have data --- Interrupt call
+{
+    if(UT.readable())  //IF data available
+    {
+        rxBuffer[bufferReadingIndex++] = UT.getc();   // read and store into Buffer
+        if(bufferReadingIndex >= BUFFER_SIZE)  // If limit cross
+        {
+            bufferReadingIndex =0; // RESET CONTER
+        }
+    }
+}
+
+void response()  //FUNCTION TO READ DATA
+{
+    char rxByte;
+
+    while(i != bufferReadingIndex)  //READ WHILE COMPLETE DATA NOT RECEIVED
+    {
+        rxByte = rxBuffer[i];  //READ DATA ONE BY ONE CHARACTER
+        pc.putc(rxByte); // SEND ON TERMINAL
+        i++;  //COUNTER INCREMENT
+        
+        if(i >= BUFFER_SIZE) //IF LIMIT CROSS
+        {
+            i = 0;   //RESET COUNTER
+        }
+    }
+}
+
+void FLUSH()            //FLUSH FUNCTIONS
+{
+    RxInterrupt(); // This is because read data if something available in UART buffer
+    
+    //Counters which are related with UART reading process make it zero again
+    i = 0U;
+    bufferReadingIndex = 0U;   
+    
+}
\ No newline at end of file