La Suno
I2C hang recover function added
Dependencies: UniGraphic mbed vt100
In this version, check_i2c_pins function was added in edge_mgr.cpp.
プログラムの起動時、I2Cモジュールを初期化する前に、I2Cに使用するピンの電位を確認し
もし一方でも Low に張り付いていた場合、SCL を GPIO 出力に設定して
所定回数 (I2C_UNLOCK_TRIAL_CYCLE) 反転させることにより、疑似リセットクロックを生成します。
その後は、通常の起動手順に復帰し、以降はこれまでと同様の動作をします。
Diff: sensors/PSE530.cpp
- Revision:
- 0:d895cd1cd897
- Child:
- 2:de22987be9ba
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sensors/PSE530.cpp Tue Apr 03 08:30:29 2018 +0000
@@ -0,0 +1,60 @@
+#include "mbed.h"
+#include "PSE530.h"
+
+/**
+ * SMC PSE530 pressure sensor
+ * analog output 1.0V - 5.0V
+ * 1.0V : 0
+ * 5.0V : 1MPa
+ * (at 0.6V : -0.1MPa)
+ * Our sensor I/F converts 0-5V to 0-3V
+ * So we suppose V = Analog Float Value : Pressure
+ * 0.6V = 0.2 : 0
+ * 3.0V = 1.0 : 1MPa
+ */
+
+ /**
+ * conversion from Pa to kgf/cm2
+ * 98,066.5 Pa = 1 kgf/cm2
+ * 1 Pa = 1 / 98066.6 kgf/cm2
+ */
+
+PSE530::PSE530(AnalogIn *ain)
+{
+ _ain = ain ;
+}
+
+PSE530::~PSE530(void)
+{
+ if (_ain) {
+ delete _ain ;
+ }
+}
+
+/**
+ * On FRDM-KL25Z ADC's AREF is about 3.28V
+ * Where the converted pressure output is 0 to 3.21V
+ * So we must map ADC output 0 to 3.21/3.28 as full scale
+ *
+ * Then according to the datasheet of PSE530
+ * when full range is 0V to 5V
+ * 1V is 0 and 5V is 1MPa which is converted to
+ * 0.642/3.28 to 3.21/3.28 ~ 0.195731 to 0.9786585.
+ * The linear equation of
+ * y = a x + b
+ * 0 = a * 0.195731 + b
+ * 1 = a * 0.978658 + b
+ * results a = 1.277, b = -0.250
+ */
+float PSE530::getPressure(void)
+{
+ float coef_A = 1.277 ;
+ float coef_B = -0.250 ;
+ float av = 0.0 ;
+ float value = 0.0 ;
+ av = coef_A * _ain->read() + coef_B ;
+// printf("Pressure ADC = %.4f\n", av) ;
+ value = 1000000 * av ; /* 1MPa at 1.0 */
+ value = value / 98066.5 ; /* Pa -> kgf/cm2 */
+ return( value ) ;
+}