reading portD as binary value

greetings,

i attempting read value of 3 hall effect sensors simutaniously using port manipulation.  the hall effect sensors attached pins 5, 6, , 7 (portd).  

code: [select]


#define hall1 7
#define hall2 6
#define hall3 5

int hallsensors[3];
int halld = b00000000;
int prevhalld = b00000000;
void setup()
{
serial.begin(9600);
pinmode(hall1, input);
pinmode(hall2, input);
pinmode(hall3, input);

}

void loop(){
 
halld = portd & b11100000;  //only interested in 5,6,7
serial.println (halld, bin);
delay (500);
if (halld != prevhalld){  //etc.....


when code runs not 8 bit representation of portd rather 1 or 0.  is variable halld reading binary number?

is there (correct) way read portx , binary number in variable?

thanks!

try changing:

code: [select]

halld = portd & b11100000;  //only interested in 5,6,7


to:

code: [select]

halld = pind & b11100000;  //only interested in 5,6,7


here reference section on direct port access:
http://www.arduino.cc/en/reference/portmanipulation

basically reading portd reads contents of output data register, reading pind reads actual input pins of port d.

lefty

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