--- /dev/null
+// Copyright (c) 2017, Tobias Mueller tm(at)tm3d.de\r
+// All rights reserved.\r
+//\r
+// Redistribution and use in source and binary forms, with or without\r
+// modification, are permitted provided that the following conditions are\r
+// met:\r
+//\r
+// * Redistributions of source code must retain the above copyright\r
+// notice, this list of conditions and the following disclaimer.\r
+// * Redistributions in binary form must reproduce the above copyright\r
+// notice, this list of conditions and the following disclaimer in the\r
+// documentation and/or other materials provided with the\r
+// distribution.\r
+// * All advertising materials mentioning features or use of this\r
+// software must display the following acknowledgement: This product\r
+// includes software developed by tm3d.de and its contributors.\r
+// * Neither the name of tm3d.de nor the names of its contributors may\r
+// be used to endorse or promote products derived from this software\r
+// without specific prior written permission.\r
+//\r
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\r
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\r
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\r
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\r
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\r
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\r
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\r
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\r
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\r
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\r
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r
+\r
+\r
+#define F_CPU 8000000UL\r
+#include <avr/io.h>\r
+#include <util/delay.h>\r
+#include "USI_TWI_Master.h"\r
+#include "SHT2xV2.h"\r
+\r
+uint8_t initSHT2x(){\r
+\r
+ I2c_StartCondition();\r
+ I2c_WriteByte(0b10000000);\r
+ I2c_WriteByte(0xFE);//Softreset \r
+ I2c_StopCondition();\r
+ //Default 12 Bit RH 14 Bit T\r
+ return 1;\r
+}\r
+\r
+uint8_t crcmove(uint8_t crc) {\r
+ uint8_t bit;\r
+ for(bit=8;bit>0;--bit) {\r
+ if (crc&0x80) crc=(crc<<1)^ 0x131;\r
+ else crc=(crc<<1);\r
+ }\r
+ return crc;\r
+}\r
+\r
+uint8_t calcCRCSHT2x(uint8_t b1, uint8_t b2) {\r
+ uint8_t crc=0;\r
+ crc^=b1;\r
+ crc=crcmove(crc);\r
+ crc^=b2;\r
+ return crcmove(crc);\r
+ \r
+}\r
+\r
+\r
+\r
+uint8_t getSHT2xHumTemp(double *temp,double *hum) {\r
+ uint8_t ret=1;\r
+ I2c_StartCondition();\r
+ I2c_WriteByte(0b10000000);\r
+ I2c_WriteByte(0xF3); //No Hold Temp\r
+ _delay_us(20);\r
+ I2c_StopCondition();\r
+ _delay_ms(85);\r
+ I2c_StartCondition();\r
+ I2c_WriteByte (0b10000001);\r
+ uint8_t t1 =I2c_ReadByte(ACK);\r
+ uint8_t t2 =I2c_ReadByte(ACK);\r
+ uint8_t tc =I2c_ReadByte(NO_ACK);\r
+ I2c_StopCondition();\r
+\r
+ I2c_StartCondition();\r
+ I2c_WriteByte(0b10000000);\r
+ I2c_WriteByte(0xF5); //No Hold Hum\r
+ _delay_us(20);\r
+ I2c_StopCondition();\r
+ _delay_ms(29);\r
+ I2c_StartCondition();\r
+ I2c_WriteByte (0b10000001);\r
+ uint8_t f1 =I2c_ReadByte(ACK);\r
+ uint8_t f2 =I2c_ReadByte(ACK);\r
+ uint8_t fc =I2c_ReadByte(NO_ACK);\r
+ I2c_StopCondition();\r
+ if (calcCRCSHT2x(t1,t2)==tc)\r
+ *temp=-46.85 + 175.72/65536 *(double)(((uint16_t)t1<<8)|(t2&0xF8));\r
+ else ret=0;\r
+ if (calcCRCSHT2x(f1,f2)==fc)\r
+ *hum=-6.0+125.0/65536*(double)(((uint16_t)f1<<8)|(f2&0xF8));\r
+ else ret=0;\r
+ return ret;\r
+}\r
+\r
tm3d / owSlave2.git / blobdiff