Reading Analog Ports and Saving in a micro SD CARD with the KL25z

Dependencies:   SDFileSystem mbed

Fork of SDFileSystem_HelloWorld by Neil Thiessen

Revision:
10:ae649a596123
Parent:
7:17ca3091939f
Child:
11:2be49b81dc0b
--- a/main.cpp	Tue Aug 12 14:59:15 2014 +0000
+++ b/main.cpp	Thu Aug 14 22:28:28 2014 +0000
@@ -1,14 +1,71 @@
 #include "mbed.h"
 #include "SDFileSystem.h"
 
+Timer timer;
 DigitalIn button(p21, PullUp);
-SDFileSystem sd(p5, p6, p7, p20, "sd", p22, SDFileSystem::SWITCH_NO, 20000000);
+SDFileSystem sd(p5, p6, p7, p20, "sd", p22, SDFileSystem::SWITCH_NO, 25000000);
+char buffer[4096];
+
+void writeTest()
+{
+    //Test write performance by creating a 1MB file
+    printf("Testing %iB write performance...", sizeof(buffer));
+    FileHandle* file = sd.open("Test File.bin", O_WRONLY | O_CREAT | O_TRUNC);
+    if (file != NULL) {
+        timer.start();
+        for (int i = 0; i < (1048576 / sizeof(buffer)); i++) {
+            if (file->write(buffer, sizeof(buffer)) != sizeof(buffer)) {
+                timer.stop();
+                printf("write error!\n");
+                timer.reset();
+                return;
+            }
+        }
+        timer.stop();
+        if (file->close())
+            printf("failed to close file!\n");
+        else
+            printf("done!\n\tResult: %.2fKB/s\n", 1024 / (timer.read_us() / 1000000.0));
+        timer.reset();
+    } else {
+        printf("failed to create file!\n");
+    }
+}
+
+void readTest()
+{
+    //Test read performance by reading the 1MB file created by writeTest()
+    printf("Testing %iB read performance...", sizeof(buffer));
+    FileHandle* file = sd.open("Test File.bin", O_RDONLY);
+    if (file != NULL) {
+        timer.start();
+        while (file->read(buffer, sizeof(buffer)) == sizeof(buffer));
+        timer.stop();
+        if (file->close())
+            printf("failed to close file!\n");
+        else {
+            if (sd.remove("Test File.bin"))
+                printf("failed to delete file!\n");
+            else
+                printf("done!\n\tResult: %.2fKB/s\n", 1024 / (timer.read_us() / 1000000.0));
+        }
+        timer.reset();
+    } else {
+        printf("failed to open file!\n");
+    }
+}
 
 int main()
 {
-    //Enable large frames for performance
+    //Configure CRC and large frames
+    sd.crc(true);
     sd.large_frames(true);
 
+    //Fill the buffer with random data for the write test
+    srand(time(NULL));
+    for (int i = 0; i < sizeof(buffer); i++)
+        buffer[i] = rand();
+
     while(1) {
         //Print the start message
         printf("\nPress the button to perform tests: ");
@@ -31,39 +88,21 @@
         printf("Sectors: %llu\n", sd.disk_sectors());
         printf("Capacity: %.1fMB\n", (sd.disk_sectors() * 512) / 1048576.0);
 
-        //Format the card
-        /*printf("Formatting card...");
+        //Mount the filesystem
+        sd.mount();
+
+        /*//Format the card
+        printf("Formatting card...");
         if (sd.format() == 0)
             printf("success!\n");
         else
             printf("failed!\n");*/
 
-        //Perform a write test
-        printf("Writing to card...");
-        FILE *fp = fopen("/sd/sdtest.txt", "w");
-        if (fp != NULL) {
-            fprintf(fp, "We're writing to an SD card!");
-            fclose(fp);
-            printf("success!\n");
-        } else {
-            printf("failed!\n");
-        }
+        //Perform a read/write tests
+        writeTest();
+        readTest();
 
-        //Perform a read test
-        printf("Reading from card...");
-        fp = fopen("/sd/sdtest.txt", "r");
-        if (fp != NULL) {
-            char c = fgetc(fp);
-            if (c == 'W')
-                printf("success!\n");
-            else
-                printf("incorrect char (%c)!\n", c);
-            fclose(fp);
-        } else {
-            printf("failed!\n");
-        }
-
-        //Delay for 0.2 seconds for simple debouncing
-        wait(0.2);
+        //Unmount the filesystem
+        sd.unmount();
     }
 }