Diff: main.cpp

Revision:

0:f125b9cfab7b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Oct 17 13:18:31 2012 +0000
@@ -0,0 +1,78 @@
+#include "mbed.h"
+
+LocalFileSystem fs ("fs");
+DigitalOut led1(LED1);
+DigitalOut led4(LED4);
+
+int main() {
+
+    int ctr=32; // 32 because the fixed size of the vector table
+    
+    printf("File patcher\n");
+
+    FILE *f1 = fopen("/fs/file.unp","rb"); // read binary
+    FILE *f2 = fopen("/fs/file.pat","wb"); // write binary
+
+    if (f1 == NULL) {
+        printf("Cant open file for reading\n");
+        while (1) {
+            led1 = !led1;
+            wait(0.2);
+        }
+    }
+
+    else {
+
+        unsigned int vector [8]; // storage for the vector table
+        unsigned int sum = 0;    //
+
+        // read first 7 words (28 bytes) into an array
+        for (int i = 0; i < 8; i++) {
+            vector[i] = 0; // zero the vector location
+            for (int j = 0; j < 4; j++) {
+                char c = fgetc(f1);         // read char from file
+                vector[i]  |= (c << (8*j)); // shift to byte location
+            }
+            sum += vector[i]; // keep a running total
+        }
+
+
+        // calculate the 2's compliment, for vector[7]
+        vector[7] = (~sum) + 1;
+
+        for (int i = 0; i < 8; i++) {
+            printf("Vector[%d] = 0x%08x\n",i,vector[i]);
+        }
+
+        printf("Sum vector = 0x%08x\n",sum);
+
+
+        // write out patched vector table
+        // read first 7 words (28 bytes) into an array
+        for (int i = 0; i < 8; i++) {
+            for (int j = 0; j < 4; j++) {
+                char c = ( vector[i] >> (8*j)) & 0xFF;
+                fputc(c,f2);         // read char from file
+            }
+        }
+
+        // read in and write remaining bytes of source binary
+        while (!feof(f1)) {
+            char c = fgetc (f1);    // read char from file
+            fputc(c,f2);            // write byte to file
+            ctr++;
+        }
+
+    }
+
+    fclose(f1);
+    fclose(f2);
+
+    printf("Done! %d bytes processed\n",ctr);
+    while (1) {
+        led4 = !led4;
+        wait(0.2);
+    }
+
+
+}