Bucky tutorial

src/main.cpp

@@ -1,30 +1,63 @@
 #include <Arduino.h>
 #include "mcp23017.h"
+#include <Wire.h>
 
 //Ignore the compiler instruction related code (the ones that start with #) if you are not attempting the optional section
 
 
 //Uncomment the statement below this line to work on the optional section
-// #define EXTERNAL_RESET_ENABLED
+//#define EXTERNAL_RESET_ENABLED
 
 #ifdef EXTERNAL_RESET_ENABLED
 #define RESET_PIN ______ //TODO: Add the pin thats doing the reset
 #endif
 
 // TODO: declare mcp23017 object
+Mcp23017 mcp(0x20); // Example declaration, modify as needed
 
 void setup() {
   // initialize Serial for printouts
   Serial.begin(115200);
   printf("Test begins\n"); 
 
+
   #ifdef EXTERNAL_RESET_ENABLED
     //TODO: Configure the digital pin acting as a reset an output pin and reset the IOExpander registers to their default values.
     //Make sure to check if it is an Active-High or Active-Low reset
   #endif
   // TODO: initialize I2C and mcp23017 object
+  Wire.begin(); // Initialize I2C
+  // Initialize MCP23017
+ uint8_t directions[8] = {
+    1, // pin 0 = input
+    1, // pin 1 = input (switch)
+    1,
+    1,
+    1,
+    1, // pin 5 = input
+    1,
+    0  // pin 7 = output (LED)
+  };  
+  mcp.begin(directions); // Set pin directions
 }
 
+
 void loop() {
-  // TODO: Write tests here
-}
+  mcp.set_state(7, HIGH); 
+  Serial.println("LED ON");
+  delay(1000);
+
+  mcp.set_state(7, LOW);  
+  Serial.println("LED OFF");
+  delay(1000);
+
+  // Read switch on pin 1
+  int switchState = mcp.get_state(5);
+  Serial.print("Switch state: ");
+  Serial.println(switchState);
+
+  delay(500);
+}
+
+
+

src/mcp23017.cpp

@@ -1,30 +1,68 @@
 #include "mcp23017.h"
 
 // TODO (optional): Define macros for useful register below:
-
+#define IODIRREG 0x00    // I/O Direction Register
+#define GPIOREG  0x12   // GPIO Register
 
 // TODO: Initialize i2cBus member
 Mcp23017::Mcp23017(int addr) {
 
+    this->addr = addr;
+
+
 }
 
 uint8_t Mcp23017::get_dir(int pin) {
-    return 0;
+    Wire.beginTransmission(addr);
+    Wire.write(IODIRREG);          // Point to IODIR register 
+    Wire.endTransmission();
+    Wire.requestFrom(addr, 1); // Request 1 byte
+    uint8_t diReg = Wire.read();
+
+    return (diReg >> pin) & 0x01;
 }
 
 
 // TODO: Read from state register
 uint8_t Mcp23017::get_state(int pin) {
-    return 0;
+   Wire.beginTransmission(addr);          // Point to GPIO register
+   Wire.write(GPIOREG);
+   Wire.endTransmission();
+    Wire.requestFrom(addr, 1); // Request 1 byte
+    uint8_t gpioreg = Wire.read();
+    return (gpioreg >> pin) & 0x01;
 }
 
+
 // TODO: Write to directions register
 int Mcp23017::set_dir(int pin, uint8_t dir) {
+    uint8_t diReg = get_dir(pin); // read current direction register
+    if(dir ==1) {
+        diReg |= (1 << pin); // set pin to input
+    } else {
+        diReg &= ~(1 << pin); // set pin to output
+    }
+    Wire.beginTransmission(addr);
+    Wire.write(IODIRREG);          // Point to IODIR register
+    Wire.write(diReg);             // Write updated direction
+    Wire.endTransmission();
+
     return 0;
 }
 
 // TODO: Write to state register
 int Mcp23017::set_state(int pin, uint8_t val) {
+   uint8_t gpioreg =  get_state(pin); // read current state register
+    if(val ==1) {
+        gpioreg |= (1 << pin); // set pin high
+    } else {
+        gpioreg &= ~(1 << pin); // set pin low
+
+    }
+    Wire.beginTransmission(addr);
+    Wire.write(GPIOREG);          // Point to GPIO register
+    Wire.write(gpioreg);             // Write updated state
+    Wire.endTransmission();
     return 0;
 }
 
@@ -34,6 +72,35 @@ int Mcp23017::begin(uint8_t directions[8]) {
     int rc;
 
     // TODO: Add device ID check
+    uint8_t iodira_val = 0;
+    for(int i=0; i<8; i++) {
+        iodira_val |= (get_dir(i) << i);
+        //iodira_val = (iodira_val << 1) | (get_dir(i));
+    }
+
+    Serial.printf("IODIRA register value: 0x%02X\n", iodira_val);
+
+    if(iodira_val != 0xFF) {
+        return 1; // Device ID mismatch
+    }
+
+    uint8_t dirByte = 0;
+    for(int i=0; i<8; i++) {
+        dirByte |= (directions[i] << i);
+    }
+    Serial.printf("Direction byte: 0x%02X\n", dirByte);
+    Wire.beginTransmission(addr);
+    Wire.write(IODIRREG);          // Point to IODIR register
+    Wire.write(dirByte);           // Set directions
+    Wire.endTransmission();
+
+
+     iodira_val = 0;
+    for(int i=0; i<8; i++) {
+        iodira_val |= (get_dir(i) << i);
+        //iodira_val = (iodira_val << 1) | (get_dir(i));
+    }
+    Serial.printf("MCP23017 initialized at address 0x%02X\n", iodira_val);
 
     return 0;
 }