Diff: main.cpp

Revision:

0:b16a9b34fa4c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Sep 06 15:17:20 2016 +0000
@@ -0,0 +1,102 @@
+
+#include "mbed.h"
+
+#include <stdint.h>
+#include "bme280.h"
+
+#if defined TARGET_LPC81X
+    // SDA, SCL for Elektor CoCo-ri-Co!
+    #define PIN_SDA  (P0_10)
+    #define PIN_SCL  (P0_11)
+#elif defined TARGET_NRF51_MICROBIT
+    // SDA, SCL for BBC micro:bit
+    #define PIN_SDA  I2C_SDA0 /* (P20) */
+    #define PIN_SCL  I2C_SCL0 /* (P19) */
+#endif
+
+I2C i2c(PIN_SDA,PIN_SCL);
+BME280 bme280;
+
+DigitalOut led1(LED1); // Blue on LPC800-MAX, Pad0 on micro:bit
+DigitalOut led2(LED2); // Green on LPC800-MAX, Pad1 on micro:bit
+DigitalOut led3(LED3); // Red on LPC800-MAX, Pad2 on micro:bit
+
+#if defined TARGET_LPC81X
+    #define LED_ON  (0)
+    #define LED_OFF  (1)
+#elif defined TARGET_NRF51_MICROBIT
+    #define LED_ON  (1)
+    #define LED_OFF  (0)
+#endif
+
+// Note for LPC800-MAX users: check SJ1 and SJ4. 
+// For the USB serial port to work pins 1&2 must be shorted, not pins 2&3.
+
+
+void i2cWrite(uint8_t i2c_address, uint8_t *p_data, uint8_t data_size, uint8_t repeated_start)
+{
+    // mbed uses 8-bit addresses, always confusing.
+    i2c.write(i2c_address<<1,(const char *)p_data,data_size,repeated_start);
+}
+
+
+void i2cRead(uint8_t i2c_address, uint8_t *p_data, uint8_t data_size)
+{
+    // mbed uses 8-bit addresses, always confusing.
+    i2c.read(i2c_address<<1,(char *)p_data,data_size);
+}
+
+
+// Not using BME280 SPI interface, provide stubs.
+void spiWrite(uint8_t *p_data, uint8_t data_size) {}
+void spiRead(uint8_t *p_data, uint8_t data_size) {}
+
+
+int main(void)
+{
+    led1 = LED_OFF;
+    led2 = LED_OFF;
+    led3 = LED_OFF;
+    
+    printf("Elektor project 150652\n");
+    printf("BME280 weather sensor\n");
+#if defined TARGET_LPC81X
+    printf("for LPC800-MAX\n");
+#elif defined TARGET_NRF51_MICROBIT
+    printf("for BBC micro:bit\n");
+#endif
+
+#if BME280_ALLOW_FLOAT!=0
+    printf("Using floating point maths\n");
+#else
+    printf("Using integer maths\n");
+#endif
+
+    if (bme280.begin(BME280_I2C_ADDRESS2)!=0)
+    {
+        printf("\n*** BME280 not found.\n");
+    }
+    printf("\n");
+    
+    // Configure for test purposes.
+    bme280.writeConfigRegister(BME280_STANDBY_500_US,BME280_FILTER_OFF,0);
+    bme280.writeControlRegisters(BME280_OVERSAMPLING_1X,BME280_OVERSAMPLING_1X,BME280_OVERSAMPLING_1X,BME280_MODE_NORMAL);
+
+    while (1)
+    {
+        led1 = LED_ON;
+ 
+        bme280.read();
+#if BME280_ALLOW_FLOAT!=0
+        printf("T=%0.1f degrees C, P=%0.1f mbar, RH=%0.1f%%\n",bme280.temperature(),bme280.pressure()/100,bme280.humidity());
+#else
+        printf("T=%d degrees C, P=%d mbar, RH=%d%%\n",bme280.temperature()/100,bme280.pressure()/100,bme280.humidity()>>10);
+#endif
+
+        // Worst case speed is about 1 Hz.
+        // Keep flash short, it is terribly bright.
+        wait_ms(5);
+        led1 = LED_OFF;
+        wait_ms(995);
+    }
+}