http://www.microsyl.com/clock/clock.html
LED Propeller Clock Based on Atmel AVR AT90S2313 MicroProcessor at 16Mhz

Propeller Analog/Digital Clock

History

I got this idea by browsing the web. I found by hazard  Mr. Bob Blick's page who make the first propeller clock.  I began to check how can I build one myself.  Base on AVR AT90S2313 I saw rapidly that my MCU must be clocked very fast to make all the calculations needed to light the leds at the right place.  The speed is at 16Mhz,  4 times faster than Atmel's specifications. It's working without any problems.

Each time the PCB passed at 12h00 an hall effect sensor sensed the magnet and generated an interruption. At this time, we have to check the counter to se how many ticks had been passed from this rotation since  the last rotation tooks this value and divide it by 360. This calculation will gives you the time between each degree.  Now, you have to set an interruption to occur at each degree and after you will be able to light leds whenever you want at any of 360 degrees.  At this MCU speed, there is no jitter everything is just FIXED!!!

A simple IR sensor is used to take the signal from the remote control (set to a Sony protocol).

Don't forget to use HIGH BRIGHTNESS LEDS 1600mcd.  Leds are not lighted very long so the mcd's power must be high.

 

Features

bullet Analog clock mode
bullet Digital clock mode
bullet Infrared clock setting with a standard universal remote control

 

Pictures

Click to enlarge

Anoalog mode

Digital mode

Stopped with flash at 1/60 sec

 

Sources codes & Shematics

-Shematic in PDF format

 




//**************************************
// Clock 16Mhz
// Version 1.0 Janvier 2002
// Sylvain Bissonnette
//**************************************

//**************************************
// I N C L U D E
//**************************************
#include <io2313v.h>
#include <macros.h>
//**************************************
// D E F I N E
//**************************************
#define TRUE 0x01
#define FALSE 0x00
#define ANALOG 0x01
#define DIGITAL 0x02
//**************************************
// I N T E R R U P T H A N D L E R
//**************************************
#pragma interrupt_handler Crossing_interrupt:2
#pragma interrupt_handler IR_interrupt:4
#pragma interrupt_handler Degre_interrupt:5
#pragma interrupt_handler Ticker_interrupt:7
//**************************************
// P R O T O T Y P E
//**************************************
void Crossing_interrupt(void);
void
Degre_interrupt(void);
void
Time(unsigned char);
void
IR_interrupt(void);
void
Ticker_interrupt(void);
void
Display(void);
void
CopyData(int Value);
void
CopyDot(void); //**************************************
// G L O B A L V A R I A B L E
//**************************************
int WeelPosition;
unsigned char
Pos;
unsigned int
Adder;

unsigned char
LatchedIrData;

unsigned char
Sec;
unsigned char
Min;
unsigned char
Hrs;

int
SecComp;
int
MinComp;
int
HrsComp;

unsigned char
ClockStyle;

unsigned char
TimeString[50];
unsigned char *
TimeStringPtr;


unsigned char
i; //**************************************
// C O N S T A N T
//**************************************
const unsigned char table[12][6] = {{ 0x3e, 0x41, 0x41, 0x41, 0x3e, 0x00 }, // 0 { 0x00, 0x21, 0x7f, 0x01, 0x00, 0x00 }, // 1 { 0x21, 0x43, 0x45, 0x49, 0x31, 0x00 }, // 2 { 0x42, 0x41, 0x51, 0x69, 0x46, 0x00 }, // 3 { 0x0c, 0x14, 0x24, 0x5f, 0x04, 0x00 }, // 4 { 0x72, 0x51, 0x51, 0x51, 0x4e, 0x00 }, // 5 { 0x1e, 0x29, 0x49, 0x49, 0x06, 0x00 }, // 6 { 0x40, 0x47, 0x48, 0x50, 0x60, 0x00 }, // 7 { 0x36, 0x49, 0x49, 0x49, 0x36, 0x00 }, // 8 { 0x30, 0x49, 0x49, 0x4a, 0x3c, 0x00 }, // 9 { 0x00, 0x36, 0x36, 0x00, 0x00, 0x00 }, // : { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }};// space


//**************************************
// M A I N
//**************************************
void main()
{
WDTCR = 0x0e; // Enable WatchDog at 0.97 sec PORTD = 0x0d; // Pull up on PD2&PD3 & Led White ON DDRD = 0x03; // PD0-O PD1-O PD2-I PD3-I PD4-I PD5-I PD6-I PD7-I

//INT 0
MCUCR = 0x02; // Int0 generate int on falling eadge GIMSK = 0x40; // Int0 enable

//Timer0
TCCR0 = 0x05; // Timer0 / 1024

//Timer1
TCCR1B = 0x42; // Timer1 / 8 & Input Capture on Rising eadge TIMSK = 0x4a; // int enable on Timer1 Compare Match
// int enable on Timer 1 Input Capture
// int enable on Timer0 Overflow
PORTB = 0x00; DDRB = 0xff; // PB0-7 as output Hrs = 0; Min = 0; Sec = 0; ClockStyle = ANALOG; SEI();

while(
1)
{
asm(
"WDR");
for (
i=0;i<200;i++);
if ((
LatchedIrData == 0xbb) || (LatchedIrData == 0x92)) Time(TRUE);
if ((
LatchedIrData == 0xb3) || (LatchedIrData == 0xb0)) ClockStyle = DIGITAL;
if ((
LatchedIrData == 0xb4) || (LatchedIrData == 0xb1)) ClockStyle = ANALOG; LatchedIrData = 0;
}
}
/**********************************************************

Name: void Time(void)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void Time(unsigned char Fast)
{
if (
Fast == FALSE) Sec++;
else
Sec += 60;
if (
Sec > 59)
{
Sec = 0; Min++;
if (
Min > 59)
{
Min = 0; Hrs++;
if (
Hrs > 11)
{
Hrs = 0;
}
}
}

if (
ClockStyle == ANALOG)
{
SecComp = Sec*6; MinComp = Min*6; HrsComp = (Hrs*30)+(Min/2);
}
else {
TimeStringPtr = &TimeString[0]; CopyData(Hrs); CopyDot(); CopyData(Min); CopyDot(); CopyData(Sec);
}
}
/**********************************************************

Name: void CopyData(int Value)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void CopyData(int Value)
{
if (
Value < 10)
{
for (
i=0;i<6;i++) *TimeStringPtr++ = table[0][i];
for (
i=0;i<6;i++) *TimeStringPtr++ = table[Value][i];
}
else { for (
i=0;i<6;i++) *TimeStringPtr++ = table[Value/10][i];
for (
i=0;i<6;i++) *TimeStringPtr++ = table[Value-((Value/10)*10)][i];
}
}
/**********************************************************

Name: void CopySpace(void)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void CopyDot(void)
{
for (
i=0;i<6;i++) *TimeStringPtr++ = table[10][i];
}
/**********************************************************

Name: void Crossing_interrupt(void

Description:

Input: none

Output: none

Misc:

**********************************************************/
void Crossing_interrupt(void)
{
static unsigned int
LastCount;
static unsigned int
TotalCount;
static int
Latch;
static unsigned char
Lap; Latch = TCNT1; TotalCount = Latch - LastCount; LastCount = Latch; Lap++;
if (
Lap > 250)
{
Adder = TotalCount / 378; Lap = 0;
}
WeelPosition = 0; OCR1 = Latch + Adder; TIFR |= 0x80; Display();
}
/**********************************************************

Name: void Degre_interrupt(void)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void Degre_interrupt(void)
{
OCR1 = TCNT1 + Adder; Display();
}
/**********************************************************

Name: void Display(void)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void Display(void)
{
PORTB = 0x00;

if (
ClockStyle == ANALOG)
{
if (
WeelPosition == HrsComp) PORTB = 0x80;
if (
WeelPosition == MinComp) PORTB = 0xff;
if (
WeelPosition == SecComp) PORTB |= 0x03;

if ((
WeelPosition == 0) ||
(
WeelPosition == 30) ||
(
WeelPosition == 60) ||
(
WeelPosition == 90) ||
(
WeelPosition == 120) ||
(
WeelPosition == 150) ||
(
WeelPosition == 180) ||
(
WeelPosition == 210) ||
(
WeelPosition == 240) ||
(
WeelPosition == 270) ||
(
WeelPosition == 300) ||
(
WeelPosition == 330)) PORTB |= 0x01;
}
else {
Pos = ((WeelPosition-100) / 3);
if (
Pos < 49)
{
PORTB = TimeString[48-Pos];
}
}
WeelPosition++;
}
/**********************************************************

Name: void IR_interrupt(void)

Description: This routine is called whenever a rising edge (beginning
of valid IR signal) is received.

- The data codes are sent using pulse coding.
- Each packet has 12 bits and a header.
- The basic time period T = 550us.
- The header length = 4T (2.2ms)
- 0 = pulse with length T followed by space of length T.
- 1 = pulse with length 2T followed by space of length T.
- The last 5 bits represent the Addess.
- The first 7 bits represent the command.
- A packet is transmitted every 25ms while a button is down.

Input: none

Output: Global variable LatchedIrData

Misc: Sony VCR protocol

**********************************************************/
void IR_interrupt(void)
{
static unsigned int
LastCapture;
unsigned int
PulseWidth;
static unsigned int
IrPulseCount;
static unsigned int
IrData; PulseWidth = ICR1 - LastCapture; LastCapture = ICR1;


if (
PulseWidth > 4000)
{
IrPulseCount = 0; IrData = 0;
}
else {
IrData = IrData >> 1;
if (
PulseWidth > 2800) IrData = IrData | 0x8000; IrPulseCount++;
if (
IrPulseCount == 12) LatchedIrData = ((IrData >> 4) & 0x00ff);
}
}
/**********************************************************

Name: void Ticker_interrupt(void)

Description:

Input: none

Output: none

Misc:

**********************************************************/
void Ticker_interrupt(void)
{
static unsigned char
Tick; Tick++;
if (
Tick > 62)
{
Time(FALSE); Tick = 0;
}
TCNT0 = 0x04; // reload counter }