diff options
Diffstat (limited to 'src/ds18b20/tm_stm32f4_ds18b20.c')
| -rw-r--r-- | src/ds18b20/tm_stm32f4_ds18b20.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/src/ds18b20/tm_stm32f4_ds18b20.c b/src/ds18b20/tm_stm32f4_ds18b20.c new file mode 100644 index 0000000..d16e48c --- /dev/null +++ b/src/ds18b20/tm_stm32f4_ds18b20.c @@ -0,0 +1,394 @@ +/**
+ * |----------------------------------------------------------------------
+ * | Copyright (C) Tilen Majerle, 2014
+ * |
+ * | This program is free software: you can redistribute it and/or modify
+ * | it under the terms of the GNU General Public License as published by
+ * | the Free Software Foundation, either version 3 of the License, or
+ * | any later version.
+ * |
+ * | This program is distributed in the hope that it will be useful,
+ * | but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * | GNU General Public License for more details.
+ * |
+ * | You should have received a copy of the GNU General Public License
+ * | along with this program. If not, see <http://www.gnu.org/licenses/>.
+ * |----------------------------------------------------------------------
+ */
+#include "tm_stm32f4_ds18b20.h"
+
+uint8_t TM_DS18B20_Start(TM_OneWire_t* OneWire, uint8_t *ROM) {
+ /* Check if device is DS18B20 */
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Start temperature conversion */
+ TM_OneWire_WriteByte(OneWire, DS18B20_CMD_CONVERTTEMP);
+
+ return 1;
+}
+
+void TM_DS18B20_StartAll(TM_OneWire_t* OneWire) {
+ /* Reset pulse */
+ TM_OneWire_Reset(OneWire);
+ /* Skip rom */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_SKIPROM);
+ /* Start conversion on all connected devices */
+ TM_OneWire_WriteByte(OneWire, DS18B20_CMD_CONVERTTEMP);
+}
+
+uint8_t TM_DS18B20_Read(TM_OneWire_t* OneWire, uint8_t *ROM, float *destination) {
+ uint16_t temperature;
+ uint8_t resolution;
+ int8_t digit, minus = 0;
+ float decimal;
+ uint8_t i = 0;
+ uint8_t data[9];
+ uint8_t crc;
+
+ /* Check if device is DS18B20 */
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+
+ /* Check if line is released, if it is, then conversion is complete */
+ if (!TM_OneWire_ReadBit(OneWire)) {
+ /* Conversion is not finished yet */
+ return 0;
+ }
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Get data */
+ for (i = 0; i < 9; i++) {
+ /* Read byte by byte */
+ data[i] = TM_OneWire_ReadByte(OneWire);
+ }
+
+ /* Calculate CRC */
+ crc = TM_OneWire_CRC8(data, 8);
+
+ /* Check if CRC is ok */
+ if (crc != data[8]) {
+ /* CRC invalid */
+ return 0;
+ }
+
+ /* First two bytes of scratchpad are temperature values */
+ temperature = data[0] | (data[1] << 8);
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+
+ /* Check if temperature is negative */
+ if (temperature & 0x8000) {
+ /* Two's complement, temperature is negative */
+ temperature = ~temperature + 1;
+ minus = 1;
+ }
+
+
+ /* Get sensor resolution */
+ resolution = ((data[4] & 0x60) >> 5) + 9;
+
+
+ /* Store temperature integer digits and decimal digits */
+ digit = temperature >> 4;
+ digit |= ((temperature >> 8) & 0x7) << 4;
+
+ /* Store decimal digits */
+ switch (resolution) {
+ case 9: {
+ decimal = (temperature >> 3) & 0x01;
+ decimal *= (float)DS18B20_DECIMAL_STEPS_9BIT;
+ } break;
+ case 10: {
+ decimal = (temperature >> 2) & 0x03;
+ decimal *= (float)DS18B20_DECIMAL_STEPS_10BIT;
+ } break;
+ case 11: {
+ decimal = (temperature >> 1) & 0x07;
+ decimal *= (float)DS18B20_DECIMAL_STEPS_11BIT;
+ } break;
+ case 12: {
+ decimal = temperature & 0x0F;
+ decimal *= (float)DS18B20_DECIMAL_STEPS_12BIT;
+ } break;
+ default: {
+ decimal = 0xFF;
+ digit = 0;
+ }
+ }
+
+ /* Check for negative part */
+ decimal = digit + decimal;
+ if (minus) {
+ decimal = 0 - decimal;
+ }
+
+ /* Set to pointer */
+ *destination = decimal;
+
+ /* Return 1, temperature valid */
+ return 1;
+}
+
+uint8_t TM_DS18B20_GetResolution(TM_OneWire_t* OneWire, uint8_t *ROM) {
+ uint8_t conf;
+
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Ignore first 4 bytes */
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+
+ /* 5th byte of scratchpad is configuration register */
+ conf = TM_OneWire_ReadByte(OneWire);
+
+ /* Return 9 - 12 value according to number of bits */
+ return ((conf & 0x60) >> 5) + 9;
+}
+
+uint8_t TM_DS18B20_SetResolution(TM_OneWire_t* OneWire, uint8_t *ROM, TM_DS18B20_Resolution_t resolution) {
+ uint8_t th, tl, conf;
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Ignore first 2 bytes */
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+
+ th = TM_OneWire_ReadByte(OneWire);
+ tl = TM_OneWire_ReadByte(OneWire);
+ conf = TM_OneWire_ReadByte(OneWire);
+
+ if (resolution == TM_DS18B20_Resolution_9bits) {
+ conf &= ~(1 << DS18B20_RESOLUTION_R1);
+ conf &= ~(1 << DS18B20_RESOLUTION_R0);
+ } else if (resolution == TM_DS18B20_Resolution_10bits) {
+ conf &= ~(1 << DS18B20_RESOLUTION_R1);
+ conf |= 1 << DS18B20_RESOLUTION_R0;
+ } else if (resolution == TM_DS18B20_Resolution_11bits) {
+ conf |= 1 << DS18B20_RESOLUTION_R1;
+ conf &= ~(1 << DS18B20_RESOLUTION_R0);
+ } else if (resolution == TM_DS18B20_Resolution_12bits) {
+ conf |= 1 << DS18B20_RESOLUTION_R1;
+ conf |= 1 << DS18B20_RESOLUTION_R0;
+ }
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Write scratchpad command by onewire protocol, only th, tl and conf register can be written */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_WSCRATCHPAD);
+
+ /* Write bytes */
+ TM_OneWire_WriteByte(OneWire, th);
+ TM_OneWire_WriteByte(OneWire, tl);
+ TM_OneWire_WriteByte(OneWire, conf);
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Copy scratchpad to EEPROM of DS18B20 */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_CPYSCRATCHPAD);
+
+ return 1;
+}
+
+uint8_t TM_DS18B20_Is(uint8_t *ROM) {
+ /* Checks if first byte is equal to DS18B20's family code */
+ if (*ROM == DS18B20_FAMILY_CODE) {
+ return 1;
+ }
+ return 0;
+}
+
+uint8_t TM_DS18B20_SetAlarmLowTemperature(TM_OneWire_t* OneWire, uint8_t *ROM, int8_t temp) {
+ uint8_t tl, th, conf;
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+ if (temp > 125) {
+ temp = 125;
+ }
+ if (temp < -55) {
+ temp = -55;
+ }
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Ignore first 2 bytes */
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+
+ th = TM_OneWire_ReadByte(OneWire);
+ tl = TM_OneWire_ReadByte(OneWire);
+ conf = TM_OneWire_ReadByte(OneWire);
+
+ tl = (uint8_t)temp;
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Write scratchpad command by onewire protocol, only th, tl and conf register can be written */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_WSCRATCHPAD);
+
+ /* Write bytes */
+ TM_OneWire_WriteByte(OneWire, th);
+ TM_OneWire_WriteByte(OneWire, tl);
+ TM_OneWire_WriteByte(OneWire, conf);
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Copy scratchpad to EEPROM of DS18B20 */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_CPYSCRATCHPAD);
+
+ return 1;
+}
+
+uint8_t TM_DS18B20_SetAlarmHighTemperature(TM_OneWire_t* OneWire, uint8_t *ROM, int8_t temp) {
+ uint8_t tl, th, conf;
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+ if (temp > 125) {
+ temp = 125;
+ }
+ if (temp < -55) {
+ temp = -55;
+ }
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Ignore first 2 bytes */
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+
+ th = TM_OneWire_ReadByte(OneWire);
+ tl = TM_OneWire_ReadByte(OneWire);
+ conf = TM_OneWire_ReadByte(OneWire);
+
+ th = (uint8_t)temp;
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Write scratchpad command by onewire protocol, only th, tl and conf register can be written */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_WSCRATCHPAD);
+
+ /* Write bytes */
+ TM_OneWire_WriteByte(OneWire, th);
+ TM_OneWire_WriteByte(OneWire, tl);
+ TM_OneWire_WriteByte(OneWire, conf);
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Copy scratchpad to EEPROM of DS18B20 */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_CPYSCRATCHPAD);
+
+ return 1;
+}
+
+uint8_t TM_DS18B20_DisableAlarmTemperature(TM_OneWire_t* OneWire, uint8_t *ROM) {
+ uint8_t tl, th, conf;
+ if (!TM_DS18B20_Is(ROM)) {
+ return 0;
+ }
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Read scratchpad command by onewire protocol */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_RSCRATCHPAD);
+
+ /* Ignore first 2 bytes */
+ TM_OneWire_ReadByte(OneWire);
+ TM_OneWire_ReadByte(OneWire);
+
+ th = TM_OneWire_ReadByte(OneWire);
+ tl = TM_OneWire_ReadByte(OneWire);
+ conf = TM_OneWire_ReadByte(OneWire);
+
+ th = 125;
+ tl = (uint8_t)-55;
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Write scratchpad command by onewire protocol, only th, tl and conf register can be written */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_WSCRATCHPAD);
+
+ /* Write bytes */
+ TM_OneWire_WriteByte(OneWire, th);
+ TM_OneWire_WriteByte(OneWire, tl);
+ TM_OneWire_WriteByte(OneWire, conf);
+
+ /* Reset line */
+ TM_OneWire_Reset(OneWire);
+ /* Select ROM number */
+ TM_OneWire_SelectWithPointer(OneWire, ROM);
+ /* Copy scratchpad to EEPROM of DS18B20 */
+ TM_OneWire_WriteByte(OneWire, ONEWIRE_CMD_CPYSCRATCHPAD);
+
+ return 1;
+}
+
+uint8_t TM_DS18B20_AlarmSearch(TM_OneWire_t* OneWire) {
+ /* Start alarm search */
+ return TM_OneWire_Search(OneWire, DS18B20_CMD_ALARMSEARCH);
+}
+
+uint8_t TM_DS18B20_AllDone(TM_OneWire_t* OneWire) {
+ /* If read bit is low, then device is not finished yet with calculation temperature */
+ return TM_OneWire_ReadBit(OneWire);
+}
+
+
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