View difference between Paste ID: 5Zv4ACai and 96emhzKi

 /*
- * FourDigitSevenSegmentDisplayDriver.c
+  Testing I2C comms to my ATtiny2313
- *
+
- * Created: 1/31/2012 1:09:17 AM
+
- *  Author: grist.carrigafoyl
+#include <Wire.h>
-
+
-Code to turn an ATtiny2313 into a 4 digit 7 segment display driver. This will
+// local LED pins
-allow offloading multiplexing a typical LED display to a slave chip and
+#define LED1 8
-let the main CPU get on with whatever it's doing. The driver displays
+#define LED2 9
-whatever is in its data register until it receives new data over the
+#define LED3 10
-serial lines.
+#define LED4 11
 
-Employs a 5 byte protocol with the first byte containing flags that control
+// Array to hold the led pin numbers
-the colon and degrees indication and also how the data is displayed
+int LEDS[4] = {LED1, LED2, LED3, LED4};
-and the other 4 bytes contain the data to be displayed.
+const int SLAVE_ADDRESS = 0x01;// this must match the address assigned to the ATtiny in its code or they won't talk
 
-Using Don Blake's translation of the Atmel I2C (TWI) library.
+// setup
 void setup() {
-First byte
+ Wire.begin();
-First 4 bits are format related
+ for (byte i=0;i<4;i++) {
-1 (128) - bit 1 of format
+   pinMode(LEDS[i], OUTPUT);
-2 (64) - bit 2 of format
+ }
-3 (32) - bit 1 of format params
+
-4 (16) - bit 2 of format params
+
-Second 4 bits are display option related (not implemented for now)
+// Main
-5 (8) - flashing (not implemented)
+void loop () {
-6 (4) - scrolling (not implemented)
+
-7 (2) - bit 1 of display option params
+  // Demonstrate each of the display modes available
-8 (1) - bit 2 of display option params
+  delay(1000);
   testRaw();
   delay(1000);
   testTime();
-#define F_CPU 8000000UL  //  8Mhz
+  delay(1000);
   testDegrees();
-#define NUM_DIGITS 4
+  delay(1000);
-#define NUM_SEGMENTS 8 // a 7 segment display has 8 segments. #8 is the decimal point
+  testDecimal();
-#define NUM_BYTES_IN_PROTOCOL 5 // how many bytes to read at a time
+  delay(1000);
 
-#include <avr/io.h>
+
-#include <util/delay.h>
+
-#include <avr/interrupt.h> // for I2C
+//-------------------------------------------------------------------
 // Functions
-#include "usiTwiSlave.h" // Don Blake's library
+//-------------------------------------------------------------------
 void testRaw() {
-// The TWI address for this slave device
+  // test the raw mode
-const uint8_t TWI_SLAVE_ADDRESS = 0x01;
+
   // A simple set of patterns to display.
-// Constants for option byte bitmapping. First 4 bits are for the display format
+  byte number_maps[15] = {
-const uint8_t FORMAT_MASK =		0b11000000;
+      //abcdefgp - 1 for on, 0 for off.
-const uint8_t FORMAT_OPTION_MASK = 0b00110000;
+      B11000111,
-// RAW format masks
+      B00111010,
-const uint8_t FORMAT_RAW =		0b00000000; // Param bits are colon & apostrophe
+      B11000110,
-const uint8_t RAW_OPTION_COLON = 0b00100000;
+      B00111010,
-const uint8_t RAW_OPTION_APOSTROPHE = 0b00010000;
+      B11000110,
-// TIME format masks
+      B00111010,
-const uint8_t FORMAT_TIME =		0b10000000; // (could have param for 24 hr? indicated by dot in pos 1)
+      B11000110,
-const uint8_t TIME_OPTION_HHMM = 0b00100000;
+      B00111010,
-const uint8_t TIME_OPTION_MMSS = 0b00010000;
+      B11000110,
-const uint8_t TIME_OPTION_SECONDS = 0b00110000;
+      B00111010,
-// DEGREES format masks
+  };
-const uint8_t FORMAT_DEGREES =	0b11000000; // Param bits are point position indicator, 0 or 1 are off, only positions 2 & 3 are valid)
+
-const uint8_t DEGREES_DOT_POS_MASK = 0b00110000;
+  byte option_byte = B00110000; // turn the colon & apostrophe on
-// DECIMAL format masks
+  for (int i=0;i<3;i++){
-const uint8_t FORMAT_DECIMAL =	0b01000000; // Param bits are point postion indicator 0 is off, 123 count from right)
+    for (byte i = 0; i<10; i++) {
-const uint8_t DECIMAL_DOT_POS_MASK = 0b00110000;
+      displayData(i); // show the current data on the locallly connected LEDs
 
-// Now the display options in the last 4 bits. Not implemented as yet.
+      Wire.beginTransmission(SLAVE_ADDRESS);
-const uint8_t OPTION_FLASHING =	0b00001000; // delay as 2 bit param. Not implemented yet
+      Wire.write(option_byte);
-const uint8_t OPTION_SCROLLING = 0b00000100; // 2 bit param for direction. Not implemented yet
+      for (int x=0;x<4;x++) {
-const uint8_t OPTION_PARAM0 = 0b00000000;
+        Wire.write(number_maps[((i+x) % 10)]);
-const uint8_t OPTION_PARAM1 = 0b00010000;
+      }
-const uint8_t OPTION_PARAM2 = 0b00100000;
+      Wire.endTransmission();
-const uint8_t OPTION_PARAM3 = 0b00110000;
+      delay(100);
     }
-// Number bitmaps. Which LEDs to light up to represent each digit
+    //delay(250);
-const uint8_t number_maps[10] = {
+  }
-    //abcdefgp - 1 for on, 0 for off.
+
-    0b11111100, // 0
+//-------------------------------------------------------------------
-    0b01100000, // 1
+void testTime() {
-    0b11011010, // 2
+  // test the time mode
-    0b11110010, // 3
+  // slave is only reading mm:ss for now
-    0b01100110, // 4
+  char option_byte = B10000000;
-    0b10110110, // 5
+  for (byte m=5;m<15;m++) {
-    0b10111110, // 6
+    for (byte s=0;s<60;s++) {
-    0b11100000, // 7
+      Wire.beginTransmission(SLAVE_ADDRESS);
-    0b11111110, // 8
+      Wire.write(option_byte);
-    0b11110110,  // 9
+      Wire.write((char)B00000001); // hours ignored for now
-};
+      Wire.write((char)m);
-const uint8_t PATTERN_c = 0b00011010; // lower case 'c' for degrees display
+      Wire.write((char)s);
       Wire.write((char)B00000100); // 10th seconds ignored for now
       Wire.endTransmission();
-// Segment to pin mapping.
+      delay(20);
-enum SEGMENT_PINS {
+
-	seg_a = _BV(PD0),
+  }
-	seg_b = _BV(PD1),
+
-	seg_c = _BV(PB6),
+//-------------------------------------------------------------------
-	seg_d = _BV(PB4),
+void testDegrees() {
-	seg_e = _BV(PB3),
+  // test the degrees mode
-	seg_f = _BV(PB2),
+
-	seg_g = _BV(PB1),
+  byte option_byte= B11100000;
-	seg_dp = _BV(PB0)
+  // just whole numbers for now. hacking 4 bytes together. If your temp
-};
+  // will never exceed 255 you can just send 3 zeros and the raw temp.
-// Digit to pin mapping.
+  for (int x=0; x<2 ; x++ ) {
-enum DIGIT_PINS {
+    for (int y=200; y<256 ; y++ ) { // cut down range for testing
-	d1 = _BV(PD3),
+      Wire.beginTransmission(SLAVE_ADDRESS);
-	d2 = _BV(PD4),
+      Wire.write(option_byte);
-	d3 = _BV(PD5),
+      Wire.write((byte)0);
-	d4 = _BV(PD6)
+      Wire.write((byte)0);
-};
+      Wire.write((byte)x);
       Wire.write((byte)y);
-// The colon and degree indicator LEDs
+      Wire.endTransmission();
-const uint8_t COLON_PIN = _BV(PA0);
+      delay(100);
-const uint8_t DEG_PIN = _BV(PA1); // degrees indicator (apostrophe)
+
   }
-// Having a delay between displaying segments helps the persistence of vision and makes the segments brighter.
+
-// Much larger than this you will see noticeable flickering, much lower and you get dimmed segments.
+
-const int POV_DELAY = 5; // ms delay for persistence of vision
+
 //-------------------------------------------------------------------
-// Digit and segment pins
+void testDecimal() {
-uint8_t digits[4] = {d1,d2,d3,d4};
+  // test the decimal mode
-// Segment pins are split over 2 ports as I2C needs 2 pins on PORTB
+  int temp;
-uint8_t portb_segment_mask = (seg_c | seg_d | seg_e | seg_f | seg_g | seg_dp);
+  for (int i=500;i<2000;i++) {
-uint8_t portd_segment_mask = (seg_a | seg_b);
+    temp = i;
-volatile uint8_t data[NUM_BYTES_IN_PROTOCOL] = {0,255,255,255,255}; // this will hold the data to be displayed
+    Wire.beginTransmission(SLAVE_ADDRESS);
     Wire.write((byte)B01110000); //option byte
-// Function prototypes
+    // the number is broken into 4 bytes. Most significant byte first.
-void displayData();
+    // Quick and dirty hack with constants.
-void showPattern(uint8_t pattern);
+    Wire.write((byte)(temp/16777216));
     temp %= 16777216;
-int main(void)
+    Wire.write((byte)(temp/65536));
-{
+    temp %= 65536;
-	// Set the pin modes for output
+    Wire.write((byte)(temp/256));
-	DDRA |= (COLON_PIN | DEG_PIN);
+    temp %= 256;
-	DDRB |= portb_segment_mask; // all pins except SDA & SCL (PB5 & 7) on PortB are output
+    Wire.write((byte)temp);
-	DDRD |= (d1 | d2 | d3 | d4 | portd_segment_mask );  // the digit selector pins & 2 of the segment pins
+    Wire.endTransmission();
-
+    delay(20);
-	// Initialise the I2C interface
+  }
-	usiTwiSlaveInit(TWI_SLAVE_ADDRESS);
+
-	// Enable global interrupts (required for I2C)
+//-------------------------------------------------------------------
-	sei();
+void displayData(byte pattern) {
  // show the current data on this device's leds.
-	// main loop
+ // first blank out the leds
-	for(;;) { // forever
+   for (byte i=0;i<4;i++) {
-		// Check to see if there's data to read in
+     digitalWrite(LEDS[i], LOW);
-		if (usiTwiDataInReceiveBuffer()) {
+   }
-			// get some bytes
+   byte pat = pattern;
-			for (int i=0;i<NUM_BYTES_IN_PROTOCOL;i++) {
+   byte i = 0;
-				data[i] = usiTwiReceiveByte();
+   while (pat > 0 && i < 4) {
-			}
+     if ((pat % 2) == 1) {
-		}
+       digitalWrite(LEDS[i], HIGH);
-		// show the current data
+     }
-		displayData();
+       pat = pat / 2;
        i++;
    }
 }