I have defined these functions below, and when I ask Device_ID function for example of the family code, I only get FF (should be 28), acctually I get both the family code, 48-bit serial, and the crc 8 bit to be all "ones". It seems like the detect slave device function works as it should.... If i connect the slave he say's I am here, and if i take it away... no device present. I also have a 5kohm pull-up at the 1wire.
And I dont have a clue why my Device_ID dont work, so my question is why doesnt it work!? can u see anything wrong within this code (Im using a PIC 18F87J50 and one DS18B20):
My statement in Main:
OSCTUNEbits.PLLEN = 1;
Init_Registers();
Init_Settings();
Init_Ports();
Init_Glcd();
Detect_Slave_Device();
Device_ID( 0x33 );
Used functions:
void Detect_Slave_Device(void){
uint8_t value;
OW_reset_pulse();
if (OW_reset_pulse())
{
Display_Cls();
Display_StringAt("No Device Present!",5,6);
Delay_1sec();
Delay_1sec();
} else {
Display_Cls();
Display_StringAt("Device Present!",5,6);
Delay_1sec();
Delay_1sec(); }}
uint8_t OW_reset_pulse(void){
uint8_t presence_detect;
drive_OW_low(); // Drive the bus low
Delay_us(200); // Delay at least 480 microsecond (us)
Delay_us(200);
Delay_us(85);
drive_OW_high (); // Release the bus
// Here should the client drive low
Delay_us(50); // Delay 50 microsecond (us)
presence_detect = read_OW(); // Sample for presence pulse from slave
Delay_us(200); // Delay 435 microsecond (us)
Delay_us(200);
Delay_us(35);
drive_OW_high (); // Release the bus
return presence_detect;}
void drive_OW_low (void){
LATHbits.LATH0 = 0;
TRISHbits.TRISH0 = 0; }// Output
void drive_OW_high (void){
LATHbits.LATH0 = 0;
TRISHbits.TRISH0 = 1;} // Input
uint8_t read_OW (void){
unsigned char read_data=0;
TRISHbits.TRISH0 = 1;
if (1 == PORTHbits.RH0)
read_data = 1;
else
read_data = 0;
return read_data;}
And now some ofthe important device_id:
void Device_ID( uint8_t command ){
uint8_t loop, family, checksum, ROM_CODE[8]; // 1 byte CRC, 6 bytes SERIAL, 1 byte Family code
static char container[1];
OW_reset_pulse();
OW_write_byte( 0x33 ); // READ ROM COMMAND DS18B20
for(loop = 0; loop < 9; loop++) // 1 byte in per time = 64-bits
{
ROM_CODE[loop] = OW_read_byte();
}
family = ROM_CODE[1];
checksum = ROM_CODE[8];
And so on = Print MY VALUES ->
void OW_write_byte (uint8_t write_data){
uint8_t loop;
for (loop = 0; loop < 8; loop++)
{
OW_write_bit(write_data & 0x01); //Sending LS-bit first
write_data >>= 1; // shift the data byte for the next bit to send
} }
void OW_write_bit (uint8_t write_bit){
if (write_bit) // Write 1 time slot
{
Brakepoint(); // 1 us
//writing a bit '1'
drive_OW_low(); // Drive the bus low
Delay_us(6); // Delay 6 microsecond (us)
drive_OW_high (); // Release the bus
Delay_us(64);; // Delay 64 microsecond (us)
}
else // Write 0 time slot
{
Brakepoint(); // 1 us
//writing a bit '0'
drive_OW_low(); // Drive the bus low
Delay_us(65); // Delay 65 microsecond (us)
drive_OW_high (); // Release the bus
Delay_us(10); // Delay 10 microsecond for recovery (us)
}}
uint8_t OW_read_byte (void)
uint8_t loop, result=0;
for (loop = 0; loop < 8; loop++)
{
result >>= 1; // shift the result to get it ready for the next bit to receive
if (OW_read_bit())
result |= 0x80; // if result is one, then set MS-bit
}
return result; }
uint8_t OW_read_bit (void){
uint8_t read_data; // Reading a bit
Brakepoint(); // 1 us
drive_OW_low(); // Drive the bus low
Delay_us(6); // delay 6 microsecond (us)
drive_OW_high (); // Release the bus
Delay_us(9); // delay 9 microsecond (us)
read_data = read_OW(); //Read the status of OW_PIN
Delay_us(55); // delay 55 microsecond (us)
return read_data;}