Diff: main.cpp

Revision:

0:ac9cb7d35d0c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Jul 11 00:56:46 2014 +0000
@@ -0,0 +1,207 @@
+/*
+ * Barometer for EA LPC11U35 QuickStart Board
+ */
+#include "mbed.h"
+#include "PCF2119.h"
+#include "BMP085.h"
+#include "WDT.h"
+
+DigitalOut myled(LED1), led_r(P0_22), led_g(P1_15), led_b(P0_23);
+I2C i2c(P0_5, P0_4);
+PCF2119 lcd(i2c, P0_21);
+BMP085 bmp(i2c, BMP085_oss8);
+Watchdog wdt;
+AnalogIn vsens(P0_11);
+DigitalOut vpwr(P0_12);
+
+float p, t, b;
+float vals[35];
+float ave = 0;
+int count = 0, ud = 0;
+
+char gaiji[5][8] = {
+    {0x0e, 0x1b, 0x11, 0x11, 0x11, 0x11, 0x1f, 0},
+    {0x0e, 0x1b, 0x11, 0x11, 0x11, 0x1f, 0x1f, 0},
+    {0x0e, 0x1b, 0x11, 0x11, 0x1f, 0x1f, 0x1f, 0},
+    {0x0e, 0x1b, 0x11, 0x1f, 0x1f, 0x1f, 0x1f, 0},
+    {0x0e, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0},
+};
+char graph[16][8];
+char updown[3] = {0x12, 0x32, 0x10};
+
+// draw screen
+void draw () {
+    int i, n;
+    float min, max, v;
+    int bit, byte;
+
+    // check min/max
+    min = vals[0];
+    max = vals[0];
+    for (i = 0; i < 35; i ++) {
+        if (vals[i] > 800 && vals[i] < 1200) {
+            if (vals[i] < min) min = vals[i];
+            if (vals[i] > max) max = vals[i];
+        }
+    }
+    min -= 0.5;
+    max += 0.5;
+    v = max - min;
+
+    // create graph
+    memset(&graph, 0, sizeof(graph));
+    bit = 1;
+    byte = 6;
+    for (i = 0; i < 35; i ++) {
+        n = (vals[i] - min) / v * 15.0;
+        if (n >= 0 && n <= 7) {
+            graph[7 + byte][7 - n] |= bit;
+        } else
+        if (n >= 8 && n <= 15) {
+            graph[byte][15 - n] |= bit;
+        }
+
+        bit = bit << 1;
+        if (bit & 0x20) {
+            bit = 1;
+            byte --;
+            if (byte < 0) break; 
+        }
+    }
+
+    // graph to font
+    for (i = 0; i < 7; i ++) {
+        lcd.cgram(i, graph[i], 8);
+        lcd.cgram(7 + i, graph[7 + i], 8);
+    }
+
+    // battery to font
+    i = (b - 2.8) / 0.1 + 0.05;
+    if (i < 0) i = 0;
+    if (i > 4) i = 4;
+    lcd.cgram(15, gaiji[i], 8);
+
+    lcd.cls();
+    // graph, pressure
+    lcd.locate(0, 0);
+    lcd.printf("\xf0\xf1\xf2\xf3\xf4\xf5\xf6%4.1fhPa", p + 0.05);
+    lcd.locate(0, 1);
+    lcd.printf("\x07\xf8\xf9\xfa\xfb\xfc\xfd  %2.1fc", t + 0.05);
+    // up/down mark
+    lcd.raw = 1;
+    lcd.locate(7, 1);
+    lcd.putc(updown[ud + 1]);
+    lcd.raw = 0;
+    // battery gauge
+    lcd.locate(15, 1);
+    lcd.printf("\xff");
+}
+
+// up/down
+void check () {
+    int i;
+    float sum;
+
+    sum = 0;
+    for (i = 0; i < 34; i ++) {
+        if (vals[i + 1] < 800 || vals[i + 1] > 1200) break;
+        sum += (vals[i] - vals[i + 1]);
+        if (sum > 1) {
+            ud = 1; // up
+            break;
+        } else
+        if (sum < -1) {
+            ud = -1; // down
+            if (i < 10) ud = -2;
+            break;
+        }
+    }
+}
+
+void sample () {
+    int i;
+
+    // BMP180
+    bmp.update();
+    p = bmp.get_pressure();
+    t = bmp.get_temperature();
+
+    ave += p;
+    count ++;
+    if (count >= 6) {
+        // average 6 min.
+        count = 0;
+        ave = ave / 6;
+        // shift buffer
+        for (i = 34; i >= 1; i --) {
+            vals[i] = vals[i - 1];
+        }
+        vals[0] = ave;
+        ave = 0;
+
+        // ADC (battery)
+        vpwr = 1;
+        wait_ms(10);
+        b = 2.495 / vsens;
+        vpwr = 0;
+
+        check();
+        draw();
+    } else {
+        lcd.locate(7, 0);
+        lcd.printf("%4.1fhPa", p + 0.05);
+        lcd.locate(9, 1);
+        lcd.printf("%2.1fc", t + 0.05);
+    }
+}
+
+int main() {
+    int w;
+
+    myled = 0;
+    led_r = led_g = led_b = 1;
+    memset(&vals, 0, sizeof(vals));
+    i2c.frequency(400000);
+
+    lcd.cls();
+    lcd.printf("Barometer");
+    led_r = 0;
+    wait_ms(300);
+    led_r = 1;
+    led_g = 0;
+    wait_ms(300);
+    led_g = 1;
+    led_b = 0;
+    wait_ms(300);
+    led_b = 1;
+
+    sample();
+    vpwr = 1;
+    wait_ms(10);
+    b = 2.495 / vsens; // battery
+    vpwr = 0;
+    draw();
+
+    for (;;) {
+        if (ud > 0) {
+            led_r = 0; // up
+        } else
+        if (ud < 0) {
+            led_b = 0; // down
+            if (ud < -1) led_g = 0;
+        } else {
+            led_g = 0;
+        }
+
+        w ++;
+        if (w >= 20) {
+            w = 0;
+            sample(); // 1 min.
+        } else {
+            wait_ms(1);
+        }
+        led_r = led_g = led_b = 1;
+        wdt.attach(NULL, 3); // wdt interrupt
+        wdt.deepSleep();
+    }
+}