static void ds1820_convert(void){
int code = 0;
portENTER_CRITICAL();
code = ds1820_reset();
if (code!= NO_ERROR)
ds1820_error(code);
ds1820_write_byte(SKIP_ROM);
ds1820_write_byte(CONVERT_TEMP);
ds1820_reset();
portEXIT_CRITICAL();
DQ_IN();
}
//#define CONSOLE_FLOAT_S( dp ,cp, var ) sprintf(cp, "%03d.%03d\r\n\0", (unsigned int)floor(var), (unsigned int)((var-floor(var))*pow(10, dp)));
static float ds1820_read_device(uint8_t * rom_code){
float retval;
uint16_t ds1820_temperature1 = 10000;
int ii;
uint8_t code = 0;
uint8_t sp1[9]; //temp to hold scratchpad memory
char c[25];
int tt = 0;
float rem = 0.0;
//portENTER_CRITICAL();
code = ds1820_reset();
if (code != NO_ERROR)
ds1820_error(code);
portENTER_CRITICAL();
ds1820_reset();
ds1820_write_byte(MATCH_ROM);
for (ii = 0; ii < 8; ii++)
{
ds1820_write_byte(rom_code[ii]);
}
ds1820_write_byte(READ_SCRATCHPAD);
for (ii = 0; ii < 9; ii++){
sp1[ii] = ds1820_read_byte();
}
ds1820_reset();
ds1820_temperature1 = sp1[1] & 0x0f;
ds1820_temperature1 <<= 8;
ds1820_temperature1 |= sp1[0];
// if the sensor is a 'B' type, we need a different conversion
if (rom_code[0] == '\x28')
{
ds1820_temperature1 >>= 4;
rem = 0.0;
if (sp1[0]&(0x01))
rem += POW_NEG_4;
if (sp1[0]&(0x02))
rem += POW_NEG_3;
if (sp1[0]&(0x04))
rem += POW_NEG_2;
if (sp1[0]&(0x08))
rem += POW_NEG_1;
retval = (float)ds1820_temperature1 + rem;
}
static uint8_t ds1820_search(){
uint8_t ii;
//char console_text[30];
ds1820_reset();
ds1820_write_byte(READ_ROM);
portENTER_CRITICAL();
for (ii = 0; ii < 8; ii++)
{
rom[ii] = ds1820_read_byte();
}
portEXIT_CRITICAL();
ds1820_reset();
return 0;
}
void ds1820_state_machine()
{
switch (ds1820_state) {
case DS1820_IDLE:
if (ds1820_reset())
return;
ds1820_write(DS1820_CMD_SKIP_ROM);
ds1820_write(DS1820_CMD_CONVERT_T);
ds1820_state = DS1820_CONVERT;
break;
case DS1820_CONVERT:
if (ds1820_read() == 0xFF)
ds1820_state = DS1820_READ;
break;
case DS1820_READ:
ds1820_read_scratchpad();
ds1820_state = DS1820_IDLE;
break;
}
}
/*Convert*/
int ds1820_convert(int sensor){
if(ds1820_reset(sensor)){
return 1;
}
ds1820_write_byte(DS1820_CMD_SKIPROM, sensor);
ds1820_write_byte(DS1820_CMD_CONVERTTEMP, sensor);
return 0;
}
/**
* Called from ds1820_refrech_all()
*/
int ds1820_get_temp(int sensor){
uint8_t scratchpad[9];
int temp_val = 0;
int temp = 0;
do{
if(ds1820_reset(sensor)){
return DS1820_TEMP_NONE;
}
ds1820_write_byte(DS1820_CMD_SKIPROM, sensor);
ds1820_write_byte(DS1820_CMD_RSCRATCHPAD, sensor);
for(int i = 0; i < 9; i++){ //Read scratchpad
ds1820_read_byte(&scratchpad[i], sensor);
}
ds1820_reset(sensor);
}while(ds1820_crc_check(scratchpad)); //while CRC matches
//temp = MSB LSB
temp_val = scratchpad[0];
temp_val |= (scratchpad[1]<<8);
temp_val <<= 7; //keep sign bit
temp_val &= 0xFF00; //clear LSB
temp_val -= 0x40; //subtract 0.25d = 40h
temp_val += (((scratchpad[7] - scratchpad[6])<<8) / scratchpad[7]);
temp = temp_val >> 8;
temp *= 10;
temp += (((temp_val & 0x00FF) * 100)>>8) / 10;
return temp;
}
//-----------------------------------------
// Read temperature
//-----------------------------------------
float ds1820_read_temp(uint8_t used_pin)
{
uint8_t error,i;
uint16_t j=0;
uint8_t scratchpad[9];
float temp=0;
scratchpad[0]=0;
scratchpad[1]=0;
scratchpad[2]=0;
scratchpad[3]=0;
scratchpad[4]=0;
scratchpad[5]=0;
scratchpad[6]=0;
scratchpad[7]=0;
scratchpad[8]=0;
error=ds1820_reset(used_pin); //1. Reset
if (error==0){
ds1820_wr_byte(0xCC,used_pin); //2. skip ROM
ds1820_wr_byte(0x44,used_pin); //3. ask for temperature conversion
while (ds1820_re_byte(used_pin)==0xFF && j<1000){ //4. wait until conversion is finished
_delay_us(1);
j++;
}
error=ds1820_reset(used_pin); //5. Reset
ds1820_wr_byte(0xCC,used_pin); //6. skip ROM
ds1820_wr_byte(0xBE,used_pin); //7. Read entire scratchpad 9 bytes
for (i=0; i<9; i++) //8. Get scratchpad byte by byte
{
scratchpad[i]=ds1820_re_byte(used_pin); //9. read one DS18S20 byte
}
}
if(scratchpad[1]==0x00 && scratchpad[7]!=0){ //Value pos.
scratchpad[0]=scratchpad[0] >> 1;
temp=(scratchpad[0]-0.25f+(((float)scratchpad[7]-(float)scratchpad[6])/(float)scratchpad[7]));
temp = (floor(temp*10.0+0.5)/10); //Round value .x
}
static void ds1820_read_scratchpad()
{
uint8_t i, crc;
ds1820_reset();
ds1820_write(DS1820_CMD_SKIP_ROM);
ds1820_write(DS1820_CMD_READ);
crc = 0;
for (i = 0; i < 9; i++) {
ds1820[i] = ds1820_read();
crc = _crc_ibutton_update(crc, ds1820[i]);
}
/* only update temperature if CRC ok */
if (!crc) {
temperature[0] = ds1820[0];
temperature[1] = ds1820[1];
}
}
////////////////////////////////////////////////////////////////////////////
// Interfacing Function
////////////////////////////////////////////////////////////////////////////
void vTaskDS1820Convert( void *pvParameters ){
char buf[30];
static char print_buf[80];
int ii = 0;
static float fTemp[NUM_SENSORS] = {0.0, 0.0}, fLastTemp[NUM_SENSORS] = {0.0, 0.0};
// initialise the bus
ds1820_init();
if (ds1820_reset() ==PRESENCE_ERROR)
{
ds1820_error(PRESENCE_ERROR);
vConsolePrint("Presence Error, Deleting DS1820 Task\r\n\0");
vTaskDelete(NULL); // if this task fails... delete it
}
// Allocate memory for sensors
b[HLT] = (char *) pvPortMalloc (sizeof(rom)+1);
b[MASH] = (char *) pvPortMalloc (sizeof(rom)+1);
// b[CABINET] = (char *) malloc (sizeof(rom)+1);
// Copy default values
memcpy(b[HLT], HLT_TEMP_SENSOR, sizeof(HLT_TEMP_SENSOR)+1);
memcpy(b[MASH], MASH_TEMP_SENSOR, sizeof(MASH_TEMP_SENSOR)+1);
// memcpy(b[CABINET], CABINET_TEMP_SENSOR, sizeof(CABINET_TEMP_SENSOR)+1);
ds1820_search();
//if (rom[0] == 0x10)
if (rom[0] != 0)
{
sprintf(print_buf, "%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x\r\n\0",rom[0],
rom[1], rom[2], rom[3], rom[4], rom[5], rom[6], rom[7]);
vConsolePrint(print_buf);
}
else
{
vConsolePrint("NO SENSOR\r\n\0");
}
for (;;)
{
ds1820_convert();
vTaskDelay(850/portTICK_RATE_MS); // wait for conversion
// save values in array for use by application
for (ii = 0 ; ii < NUM_SENSORS; ii++)
{
fTemp[ii] = ds1820_read_device(b[ii]);
if (fTemp[ii] < 105.0 && fTemp[ii] > 0.0)
{
if ((fTemp[ii] < (temps[ii] + 5.0)) || (fTemp[ii] > (temps[ii] - 5.0)) || (fTemp[ii] <= 85.0 && fTemp[ii] >= 86.0))
{
portENTER_CRITICAL(); // so that other task cannot access temps[] while we are saving.
temps[ii] = fTemp [ii];
portEXIT_CRITICAL();
}
}
if (fTemp[ii] == 0.0)
{
vConsolePrint("zero values. Temp Bus Resetting\r\n\0");
ds1820_power_reset();
ds1820_reset();
}
}
taskYIELD();
}
}
