Diff: main.cpp

Revision:

0:c1245c18d07e

Child:

1:876e9cc9088b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Mar 13 21:51:12 2017 +0000
@@ -0,0 +1,86 @@
+#include "mbed.h"
+
+//#include "uLCD_4DGL.h"
+
+Serial pc(USBTX, USBRX);
+
+InterruptIn chA(p26);
+InterruptIn chB(p25);
+int chanA;
+int chanB;
+int currState;
+int prevState;
+int change;
+
+
+//uLCD_4GDL uLCD(p9,p10,p11);
+volatile int count1 = 0;
+//volatile int count2 = 0;
+InterruptIn pb(p21);
+DigitalOut led(LED1);
+
+
+/*
+Implemented barebones version of "QEI.h" by Aaron Berk for the sake of
+understanding the concept of X4 encoding
+00 01 11 10 00
+4 different states
+*/
+
+void encode() {
+    change = 0;
+    chanA  = chA.read();
+    chanB  = chB.read();
+    currState = (chanA << 1) | (chanB);
+    if (((currState ^ prevState) != 0x3) && (currState != prevState)) {
+        // example 01 <- 11
+        // change = (11&01 = 01) ^ (01&10 = 00>>1) = 1
+        // example 10 -> 00
+        // change = (10&01 = 00) ^ (00&10 = 00>>1) = 0
+        // change = (if(left)    ^
+
+        change = (prevState & 0x1) ^ ((currState & 0x2) >> 1);
+        if (change == 0) {
+            change = -1;
+        }
+        count1 += change;
+    }
+    prevState = currState;
+}
+void clear() {
+    //uLCD.cls();
+    led = !led;
+}
+
+int main() {
+    chA.mode(PullUp);
+    chB.mode(PullUp);
+
+    chanA = chA.read();
+    chanB = chB.read();
+    currState = (chanA << 1) | (chanB);
+    prevState = currState;
+    chA.rise(&encode);
+    chA.fall(&encode);
+    chB.rise(&encode);
+    chB.fall(&encode);
+
+
+    pb.mode(PullUp);
+    pb.fall(&clear); //pb to clear screen
+    //add a pb to turn on and off pen
+    //add a pot to go through colors
+    //have something display current color and RGB val
+    while(1) {
+        /*if(count1 < 0) {
+            pc.printf("CW \n\r");
+        } else {
+            pc.printf("CCW \n\r");
+        }*/
+
+        pc.printf("count1: %d\r\n", count1);
+        pc.printf("change: %d\r\n", change);
+        pc.printf("---------\r\n");
+        wait(.1);
+    }
+}
\ No newline at end of file