Hans Oppermann
Reading temperature from DS1631 via I2C
Revision 0:b65d2cdf2cc8, committed 2014-03-25
- Comitter:
- hoteloskar
- Date:
- Tue Mar 25 15:20:27 2014 +0000
- Commit message:
- First version
Changed in this revision
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Tue Mar 25 15:20:27 2014 +0000
@@ -0,0 +1,47 @@
+#include "mbed.h"
+
+/***********************************************************************
+* Read temperature by using DS1631
+*
+* Normal I2C-protocol (start,write,..,stop) does NOT work
+* It has to be used
+* i2c.write(address,data,length,repeat)
+* which includes start and stop and a special addressing function
+************************************************************************/
+DigitalOut myled(LED2);
+DigitalIn button(USER_BUTTON);
+I2C i2c (PB_9,PB_8); // sda, scl
+
+int main() {
+ int data;
+ uint16_t cr1;
+ int ack;
+ char data_write[2];
+ char data_read[2];
+ //cr1 = I2C1->CR1;
+ //I2C1->CR2 = 0x0002;
+
+ data_write[0] = 0xEE;
+ ack = i2c.write(0x90, data_write, 1, 0);
+ data_write[0] = 0xAC; // writes the 1-byte configuration register
+ data_write[1] = 0x0F; // 1shot;12bit;pol=1
+ ack = i2c.write(0x90, data_write, 2, 0);
+
+ while(1) {
+ while (button); // start measurement by user_button
+
+ data_write[0] = 0x51; // Initiates temperature conversions
+ ack = i2c.write(0x90, data_write, 1, 0);
+ //printf("%d\n",ack);
+ wait_ms(1000);
+
+ data_write[0] = 0xAA; // Reads last converted temperature value from the 2-byte temperature register
+ ack = i2c.write(0x90, data_write, 1, 1);
+ i2c.read(0x90, data_read, 2, 0);
+
+ data=data_read[0]*100;
+ data=data+(((data_read[1] >> 4 )* 50)/8);
+ printf("%d\n",data);
+ //wait_ms(1000);
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Tue Mar 25 15:20:27 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/ed8466a608b4 \ No newline at end of file