I am having an issue with long integers. I am using a Duemilanove board. I feel that I must have a setting wrong. I've pared it down to the most minimal. I am reading a string value from a file and want to operate on it as an unsigned long. In this example, the string in question is "0x00DC143C". Whenever I try to do anything with the top 16 bits, they are ignored.
#include <SPI.h>
#include <SD.h>
#define SIZEOF_HEXLONG 12
void setup() {
// put your setup code here, to run once:
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
Serial.println("Initializing...");
char pvBuffer1[SIZEOF_HEXLONG] = "0x00DC143C";
char pvBuffer2[SIZEOF_HEXLONG] = "0x00DC";
char pvBuffer3[SIZEOF_HEXLONG] = "0x143C";
char buffer[60];
Serial.print("Pixel String Input is: ");
Serial.println(pvBuffer1);
unsigned long PixelValue = (unsigned long)strtol(pvBuffer1,0,0);
sprintf(buffer, "Full Char buffer PixelValue is 0x%08x!", PixelValue);
Serial.println(buffer);
unsigned long PixelValue2 = (unsigned long)strtol(pvBuffer2,0,0);
unsigned long PixelValue3 = (unsigned long)strtol(pvBuffer3,0,0);
sprintf(buffer, "Top Half PixelValue is 0x%08x!", PixelValue2);
Serial.println(buffer);
sprintf(buffer, "Bottom Half PixelValue is 0x%08x!", PixelValue3);
Serial.println(buffer);
unsigned long PixelValue4 = (unsigned long)((PixelValue2<<16) + PixelValue3);
sprintf(buffer, "Merged PixelValue is 0x%08x!", PixelValue3);
Serial.println(buffer);
}
void loop() {
// put your main code here, to run repeatedly:
}```
This is the serial output:
Initializing...
Pixel String Input is: 0x00DC143C
Full Char buffer PixelValue is 0x0000143c!
Top Half PixelValue is 0x000000dc!
Bottom Half PixelValue is 0x0000143c!
Merged PixelValue is 0x0000143c!
I have come up with some ideas for work-arounds and am willing to buy a new board if I have to, but this seems like such an easy issue so it must be a configuration error or something. Thank you in advance!
