Diff: main.cpp

Revision:

0:ee637039cb58

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Oct 16 06:56:41 2013 +0000
@@ -0,0 +1,99 @@
+// LCD_Spectrum_Analyzer
+// Created by Chris Wilson
+// 10/16/2013
+
+// NOTE: Contains LCD Custom Character code from Lluis Nadal
+
+#include "mbed.h"
+#include "MSGEQ7.h"
+#include "TextLCD.h"
+
+#define MAX 15
+
+MSGEQ7 eq(p13, p14, p15); //reset, strobe, analog
+TextLCD lcd(p30, p29, p28, p27, p26, p25); // rs, e, d4-d7
+
+// Defines LCD bus to write data.
+BusOut Lcd_pins(p28, p27, p26, p25); // d4, d5, d6, d7
+DigitalOut rs_pin(p30); // LCD pin rs (register select.)
+DigitalOut e_pin(p29);  // LCD pin e (enable).
+
+//This data is 8 LCD characters representing an 8-level bar graph
+char levels[8][8] = {
+    {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x1F},
+    {0x00,0x00,0x00,0x00,0x00,0x00,0x1F,0x1F},
+    {0x00,0x00,0x00,0x00,0x00,0x1F,0x1F,0x1F},
+    {0x00,0x00,0x00,0x00,0x1F,0x1F,0x1F,0x1F},
+    {0x00,0x00,0x00,0x1F,0x1F,0x1F,0x1F,0x1F},
+    {0x00,0x00,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F},
+    {0x00,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F},
+    {0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F}
+};
+
+/* Code from Lluis Nadal
+http://mbed.org/users/lnadal/code/Lcd_Custom_Char/
+*/
+// Because we use 4 bit LCD, data must be sent in two steps.
+void writePort(int value) {
+
+    Lcd_pins = value >> 4;  // Shifts 4 bit right.
+    wait(0.000040f); // Wait 40us.
+    e_pin = 0;
+    wait(0.000040f);
+    e_pin = 1;
+    Lcd_pins = value;
+    wait(0.000040f);
+    e_pin = 0;
+    wait(0.000040f);
+    e_pin = 1;
+}
+
+/* Code from Lluis Nadal
+http://mbed.org/users/lnadal/code/Lcd_Custom_Char/
+*/
+void createChars(){
+    for (int j=0; j<8; j++) {
+        rs_pin = 0; // We send a command.
+
+        /* 0X40 is the initial CGRAM address. Because each character needs a total amount of 8 memory 
+        locations, we increment addres in 8 units after each character.
+        */
+        writePort(0x40+8*j);
+
+        // Writes data.
+        rs_pin = 1; // We send data.
+        
+        for (int i=0; i<8; i++) {
+            writePort(levels[j][i]);
+        }
+    }
+}
+
+
+int main() {
+    int i = 0;
+    lcd.cls();
+    createChars();
+    
+    while(1) {
+        eq.readInt(MAX); //Read in frequency data, mapped to a max number of 15
+        
+        for(i = 0; i < 7; i++){
+            
+            lcd.locate(i, 1); //Draw second (lower) row first
+            if(eq.freqDataInt[i] > 7){ //Is the lower level maxed out?
+                lcd.putc(7); // If maxed out, display full bars
+            }else{
+                lcd.putc(eq.freqDataInt[i]);
+            }
+            
+            lcd.locate(i, 0); //Draw first (upper) row
+            if(eq.freqDataInt[i] < 8){
+                lcd.putc(32); //If empty, draw a space (' ')
+            }else{
+                lcd.putc(eq.freqDataInt[i] - 8);
+            }
+        }
+        
+    }
+}