Dai Yokota / TC77

TC77 --- SPI Thermal Sensor

Dependents:   tc77_sample

TC77 SPI thermal(temperature) sensor chip

ライブラリを公開する手順の練習を兼ねて、サンプルプログラムとして公開していた物からライブラリ部分を分離してみました。

温度センサの TC77 を使うためのライブラリです。 SPIなのにIOが共通になっているという変わったチップです。
MOSIとMISOを抵抗で繋いでしまうというのがポイントで、それさえ解れば難しいトコはありません。

pin connection

mbed                 TC77
MOSI ---R 10K---+
                |
MISO -----------+--- SI/O
SCK  --------------- SCK
CS   --------------- CS(active low)

TC77.h@0:b8fa872b60e6, 2016-06-10 (annotated)

Committer:
jk1lot
Date:
Fri Jun 10 14:27:27 2016 +0000
Revision:
0:b8fa872b60e6
first published version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jk1lot 0:b8fa872b60e6 1 /*
jk1lot 0:b8fa872b60e6 2 * TC77 SPI Thermal Sensor
jk1lot 0:b8fa872b60e6 3 *
jk1lot 0:b8fa872b60e6 4 * mbed TC77
jk1lot 0:b8fa872b60e6 5 * MOSI ---R 10K---+
jk1lot 0:b8fa872b60e6 6 * |
jk1lot 0:b8fa872b60e6 7 * MISO -----------+--- pin1 SI/O.
jk1lot 0:b8fa872b60e6 8 * SCK --------------- pin2 SCK.
jk1lot 0:b8fa872b60e6 9 * CS --------------- pin7 CS(active low).
jk1lot 0:b8fa872b60e6 10 *
jk1lot 0:b8fa872b60e6 11 */
jk1lot 0:b8fa872b60e6 12
jk1lot 0:b8fa872b60e6 13 #ifndef TC77_H
jk1lot 0:b8fa872b60e6 14 #define TC77_H
jk1lot 0:b8fa872b60e6 15
jk1lot 0:b8fa872b60e6 16 #include "mbed.h"
jk1lot 0:b8fa872b60e6 17
jk1lot 0:b8fa872b60e6 18 /** TC77 SPI Thermal Sensor chip
jk1lot 0:b8fa872b60e6 19 *
jk1lot 0:b8fa872b60e6 20 * @note pin connection
jk1lot 0:b8fa872b60e6 21 * @code
jk1lot 0:b8fa872b60e6 22 * mbed TC77device
jk1lot 0:b8fa872b60e6 23 * MOSI ---R 10K---+
jk1lot 0:b8fa872b60e6 24 * |
jk1lot 0:b8fa872b60e6 25 * MISO -----------+--- pin1 SI/O
jk1lot 0:b8fa872b60e6 26 * SCK --------------- pin2 SCK
jk1lot 0:b8fa872b60e6 27 * CS --------------- pin7 CS(active low)
jk1lot 0:b8fa872b60e6 28 * @endcode
jk1lot 0:b8fa872b60e6 29 *
jk1lot 0:b8fa872b60e6 30 @note sample program
jk1lot 0:b8fa872b60e6 31 @code
jk1lot 0:b8fa872b60e6 32 #include "mbed.h"
jk1lot 0:b8fa872b60e6 33 #include "TC77.h"
jk1lot 0:b8fa872b60e6 34
jk1lot 0:b8fa872b60e6 35 SPI spi1(p5,p6,p7);
jk1lot 0:b8fa872b60e6 36 TC77 tc77(&spi1, p8);
jk1lot 0:b8fa872b60e6 37
jk1lot 0:b8fa872b60e6 38 int main() {
jk1lot 0:b8fa872b60e6 39 while(true) {
jk1lot 0:b8fa872b60e6 40 printf("%.1f \r\n",tc77.temperature());
jk1lot 0:b8fa872b60e6 41 wait(1.0);
jk1lot 0:b8fa872b60e6 42 }
jk1lot 0:b8fa872b60e6 43 }
jk1lot 0:b8fa872b60e6 44 @endcode
jk1lot 0:b8fa872b60e6 45 */
jk1lot 0:b8fa872b60e6 46 class TC77
jk1lot 0:b8fa872b60e6 47 {
jk1lot 0:b8fa872b60e6 48 SPI *spi;
jk1lot 0:b8fa872b60e6 49 DigitalOut cs;
jk1lot 0:b8fa872b60e6 50 public:
jk1lot 0:b8fa872b60e6 51 //! @param s pointer to SPI object
jk1lot 0:b8fa872b60e6 52 //! @param pin PinName of CS
jk1lot 0:b8fa872b60e6 53 TC77(SPI *s, PinName pin);
jk1lot 0:b8fa872b60e6 54
jk1lot 0:b8fa872b60e6 55 //! go to shutdown mode(power save)
jk1lot 0:b8fa872b60e6 56 inline void shutdown(void) {write(0xffff);}
jk1lot 0:b8fa872b60e6 57 //! start from shutdown mode
jk1lot 0:b8fa872b60e6 58 void start(void);
jk1lot 0:b8fa872b60e6 59 //! get device ID
jk1lot 0:b8fa872b60e6 60 uint16_t id(void);
jk1lot 0:b8fa872b60e6 61 //! get temperature @return Temperature value, expressed in degrees Celsius
jk1lot 0:b8fa872b60e6 62 float temperature(void);
jk1lot 0:b8fa872b60e6 63 protected:
jk1lot 0:b8fa872b60e6 64 //! read data and send command.
jk1lot 0:b8fa872b60e6 65 //! It is impossible in the TC77 to perform the writing and reading at the same time.
jk1lot 0:b8fa872b60e6 66 //! After reading 16bit, TC77 is ready to write. So total transferred bit is 32.
jk1lot 0:b8fa872b60e6 67 int16_t write(int16_t command);
jk1lot 0:b8fa872b60e6 68 //! read data.
jk1lot 0:b8fa872b60e6 69 //! transferred 16bit only
jk1lot 0:b8fa872b60e6 70 int16_t read(void);
jk1lot 0:b8fa872b60e6 71 };
jk1lot 0:b8fa872b60e6 72
jk1lot 0:b8fa872b60e6 73 #endif