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Senso_3
Diff: main.cpp
- Revision:
- 5:887081decd5c
- Parent:
- 4:dcdcb25d1069
- Child:
- 6:6c1c38d4faa4
diff -r dcdcb25d1069 -r 887081decd5c main.cpp --- a/main.cpp Sat Mar 13 13:49:08 2021 +0100 +++ b/main.cpp Sat Mar 13 15:21:09 2021 +0100 @@ -1,16 +1,18 @@ #include "mbed.h" #include "platform/mbed_thread.h" - +#include "iostream" +#include "string" #include "BufferedSerial.h" +#include <math.h> +#include <stdio.h> #define pi 3.14159265358979323846 using namespace std::chrono; -InterruptIn user_button(USER_BUTTON); -DigitalOut led(LED1); -// Serial pc(SERIAL_TX, SERIAL_RX); - BufferedSerial pc(USBTX, USBRX); +InterruptIn user_button(USER_BUTTON); +DigitalOut led(LED1); +BufferedSerial pc(USBTX, USBRX); bool executeMainTask = false; Timer user_button_timer, loop_timer; @@ -19,6 +21,10 @@ void button_fall(); // stuff void button_rise(); // stuff +void reverse(char* str, int len); +int intToStr(int x, char str[], int d); +void ftoa(float n, char* res, int afterpoint); + AnalogIn analogIn(PA_0); float dist = 0.0f; @@ -38,22 +44,40 @@ // printf("measurement: %d\r\n", (static_cast<int>(dist * 1000))); Timer s; + + s.start(); + char res0[20]; + float val0 = 233.007; + ftoa(val0, res0, 4); + pc.write(res0, sizeof(res0)); + int buffered_time_ftoa = duration_cast<milliseconds>(s.elapsed_time()).count(); + thread_sleep_for(100); - s.start(); + s.reset(); + char res1[20]; + float val1 = 233.007; + ftoa(val1, res1, 4); + printf("%s\r\n", res1); + int polled_time_ftoa = duration_cast<milliseconds>(s.elapsed_time()).count(); + thread_sleep_for(100); + + s.reset(); char msg[] = "Hello World - buffered\n"; pc.write(msg, sizeof(msg)); int buffered_time = duration_cast<milliseconds>(s.elapsed_time()).count(); - thread_sleep_for(100);; // give time for the buffer to empty + thread_sleep_for(100); s.reset(); printf("Hello World - blocking\n"); int polled_time = duration_cast<milliseconds>(s.elapsed_time()).count(); s.stop(); - thread_sleep_for(100);; // give time for the buffer to empty + thread_sleep_for(100); + printf("printf buffered took %d us\n", buffered_time_ftoa); + printf("printf blocking took %d us\n", polled_time_ftoa); printf("printf buffered took %d us\n", buffered_time); printf("printf blocking took %d us\n", polled_time); - thread_sleep_for(100);; // give time for the buffer to empty + thread_sleep_for(100); @@ -82,4 +106,58 @@ int t_button = duration_cast<milliseconds>(user_button_timer.elapsed_time()).count(); user_button_timer.stop(); if(t_button > 200) executeMainTask = !executeMainTask; -} \ No newline at end of file +} + +void reverse(char* str, int len) +{ + int i = 0, j = len - 1, temp; + while (i < j) { + temp = str[i]; + str[i] = str[j]; + str[j] = temp; + i++; + j--; + } +} + +int intToStr(int x, char str[], int d) +{ + int i = 0; + while (x) { + str[i++] = (x % 10) + '0'; + x = x / 10; + } + + // If number of digits required is more, then + // add 0s at the beginning + while (i < d) + str[i++] = '0'; + + reverse(str, i); + str[i] = '\0'; + return i; +} + +void ftoa(float n, char* res, int afterpoint) +{ + // Extract integer part + int ipart = (int)n; + + // Extract floating part + float fpart = n - (float)ipart; + + // convert integer part to string + int i = intToStr(ipart, res, 0); + + // check for display option after point + if (afterpoint != 0) { + res[i] = '.'; // add dot + + // Get the value of fraction part upto given no. + // of points after dot. The third parameter + // is needed to handle cases like 233.007 + fpart = fpart * pow(10, afterpoint); + + intToStr((int)fpart, res + i + 1, afterpoint); + } +} \ No newline at end of file