uint32_t OneWire_Init( void ) {
printf("\n%s called",__FUNCTION__);
printf("\nScanning 1-wire bus...");
tempidx = -1; // Assume we don't find a temperature sensor
for( int i = 0; i < sizeof(tcidmapping); i++ ) {
tcidmapping[i] = -1; // Assume we don't find any thermocouple interfaces
}
int rslt = OWFirst();
numowdevices = 0;
while (rslt && numowdevices < MAX_OW_DEVICES) {
memcpy(owdeviceids[numowdevices], ROM_NO, sizeof(ROM_NO));
numowdevices++;
rslt = OWNext();
}
if(numowdevices) {
for( int iter = 0; iter < numowdevices; iter++ ) {
printf("\n Found ");
for( int idloop = 7; idloop >= 0; idloop-- ) {
printf("%02x", owdeviceids[iter][idloop]);
}
uint8_t family = owdeviceids[iter][0];
if(family == OW_FAMILY_TEMP) {
selectdevbyidx(iter);
xferbyte(OW_WRITE_SCRATCHPAD);
xferbyte(0x00);
xferbyte(0x00);
xferbyte(0x1f); // Reduce resolution to 0.5C to keep conversion time reasonable
tempidx = iter; // Keep track of where we saw the last/only temperature sensor
printf(" [Temperature sensor]");
} else if(family == OW_FAMILY_TC) {
selectdevbyidx(iter);
xferbyte(OW_READ_SCRATCHPAD);
xferbyte(0xff);
xferbyte(0xff);
xferbyte(0xff);
xferbyte(0xff);
uint8_t tcid = xferbyte(0xff) & 0x0f;
tcidmapping[tcid] = iter; // Keep track of the ID mapping
printf(" [Thermocouple interface, ID %x]",tcid);
}
}
} else {
printf(" No devices found!");
}
return numowdevices;
}
int OneWire_PerformTemperatureConversion(void) {
uint8_t scratch[9];
if(resetbus()) {
xferbyte(OW_SKIP_ROM); // All devices on the bus are addressed here
xferbyte(OW_CONVERT_T);
setpin1();
BusyWait8(94000<<3); // For 9-bit resolution
for( int i = 0; i < numowdevices; i++ ) {
selectdevbyidx(i);
xferbyte(OW_READ_SCRATCHPAD);
for(uint32_t iter=0; iter<2; iter++) { // Only read two bytes
scratch[iter] = xferbyte(0xff);
//printf("%02x ",scratch[iter]);
}
int16_t tmp = scratch[1]<<8 | scratch[0];
devreadout[i] = tmp;
}
} else {
BusyWait8(94000<<3); // Maintain timing if no sensors are found for the time being
}
return numowdevices;
}
static int32_t OneWire_Work(void) {
static uint8_t mystate = 0;
uint8_t scratch[9];
int32_t retval = 0;
if (mystate == 0) {
uint32_t save = VIC_DisableIRQ();
if (resetbus()) {
xferbyte(OW_SKIP_ROM); // All devices on the bus are addressed here
xferbyte(OW_CONVERT_T);
setpin1();
//retval = TICKS_MS(94); // For 9-bit resolution
retval = TICKS_MS(100); // TC interface needs max 100ms to be ready
mystate++;
}
VIC_RestoreIRQ( save );
} else if (mystate == 1) {
for (int i = 0; i < numowdevices; i++) {
uint32_t save = VIC_DisableIRQ();
selectdevbyidx(i);
xferbyte(OW_READ_SCRATCHPAD);
for (uint32_t iter = 0; iter < 4; iter++) { // Read four bytes
scratch[iter] = xferbyte(0xff);
}
VIC_RestoreIRQ(save);
int16_t tmp = scratch[1]<<8 | scratch[0];
devreadout[i] = tmp;
tmp = scratch[3]<<8 | scratch[2];
extrareadout[i] = tmp;
}
mystate = 0;
} else {
retval = -1;
}
return retval;
}
uint32_t OneWire_Init(void) {
printf("\n%s called", __FUNCTION__);
Sched_SetWorkfunc(ONEWIRE_WORK, OneWire_Work);
printf("\nScanning 1-wire bus...");
tempidx = -1; // Assume we don't find a temperature sensor
for (int i = 0; i < sizeof(tcidmapping); i++) {
tcidmapping[i] = -1; // Assume we don't find any thermocouple interfaces
}
uint32_t save = VIC_DisableIRQ();
int rslt = OWFirst();
VIC_RestoreIRQ( save );
numowdevices = 0;
while (rslt && numowdevices < MAX_OW_DEVICES) {
memcpy(owdeviceids[numowdevices], ROM_NO, sizeof(ROM_NO));
numowdevices++;
save = VIC_DisableIRQ();
rslt = OWNext();
VIC_RestoreIRQ( save );
}
if (numowdevices) {
for (int iter = 0; iter < numowdevices; iter++) {
printf("\n Found ");
for (int idloop = 7; idloop >= 0; idloop--) {
printf("%02x", owdeviceids[iter][idloop]);
}
uint8_t family = owdeviceids[iter][0];
if (family == OW_FAMILY_TEMP1 || family == OW_FAMILY_TEMP2 || family == OW_FAMILY_TEMP3) {
const char* sensorname = "UNKNOWN";
if (family == OW_FAMILY_TEMP1) {
sensorname = "DS1822";
} else if (family == OW_FAMILY_TEMP2) {
sensorname = "DS18B20";
} else if (family == OW_FAMILY_TEMP3) {
sensorname = "DS18S20";
}
save = VIC_DisableIRQ();
selectdevbyidx(iter);
xferbyte(OW_WRITE_SCRATCHPAD);
xferbyte(0x00);
xferbyte(0x00);
xferbyte(0x1f); // Reduce resolution to 0.5C to keep conversion time reasonable
VIC_RestoreIRQ(save);
tempidx = iter; // Keep track of where we saw the last/only temperature sensor
printf(" [%s Temperature sensor]", sensorname);
} else if (family == OW_FAMILY_TC) {
save = VIC_DisableIRQ();
selectdevbyidx(iter);
xferbyte(OW_READ_SCRATCHPAD);
xferbyte(0xff);
xferbyte(0xff);
xferbyte(0xff);
xferbyte(0xff);
uint8_t tcid = xferbyte(0xff) & 0x0f;
VIC_RestoreIRQ( save );
tcidmapping[tcid] = iter; // Keep track of the ID mapping
printf(" [Thermocouple interface, ID %x]",tcid);
}
}
} else {
printf(" No devices found!");
}
if (numowdevices) {
Sched_SetState(ONEWIRE_WORK, 2, 0); // Enable OneWire task if there's at least one device
}
return numowdevices;
}
