21
21
* along with this program. If not, see <http://www.gnu.org/licenses/>.
24
/******************************************************************************
28
* a PC fan is wired up to a 12V power supply
30
* the fan's SENSE (tachiometer) pin connected to pin 2 on the
33
* the pins 4 to 13 on the arduino should directly drive an LED (the
34
LED on pin 4 is in the centre of the clock face and the LED on pin
37
* if a longer hand (and a larger clock face) is desired, pin 4 can be
38
used to indirectly drive a transistor which in turn drives several
39
LEDs that turn on anf off in unison in the centre of the clock.
41
* a button should be attached to pin 3 that grounds it when pressed.
43
* A DS1307 remote clock is connected via I2C on analog pins 4 and 5.
45
Implementation details:
47
* for a schematic, see ../project/propeller-clock.sch.
49
* the timing of the drawing of the clock face is recalculated with
50
every rotation of the propeller.
52
* a PC fan actually sends 2 tachiometer pulses per revolution, so the
53
software skips every other one. This means that the clock may
54
appear upside-down if started with the propeller in the wrong
55
position. You will need to experiment to dicsover the position that
56
the propeller must be in when starting the clock.
60
* pressing the button cycles between variations of the current
63
* pressing and holding the button for a second cycles between display
64
modes (e.g., analogue and digital).
66
* pressing and holding the button for 5 seconds enters "time set"
67
mode. In this mode, the following applies:
68
- the field that is being set flashes
69
- pressing the button increments the field currently being set
70
- pressing and holding the button for a second cycles through the
71
fields that can be set
72
- pressing and holding the button for 5 seconds sets the time and
75
******************************************************************************/
82
24
//_____________________________________________________________________________
98
40
static unsigned long segment_step_sub_step = 0;
99
41
static unsigned long segment_step_sub = 0;
101
// flag to indicate that the drawing mode should be cycled to the next one
102
static bool inc_draw_mode = false;
104
// a bounce-managed button
105
static Bounce button( 3, 5 );
108
static int time_hours = 0;
109
static int time_minutes = 0;
110
static int time_seconds = 0;
112
// number of segments in a full display (rotation) is 60 (one per
113
// second) times the desired number of sub-divisions of a second
114
#define NUM_SECOND_SEGMENTS 5
115
#define NUM_SEGMENTS ( 60 * NUM_SECOND_SEGMENTS )
117
47
//_____________________________________________________________________________
121
// check for button presses
127
// notice button presses
128
if( button.risingEdge() )
129
inc_draw_mode = true;
133
// keep track of time
136
// previous time and any carried-over milliseconds
137
static unsigned long last_time = millis();
138
static unsigned long carry = 0;
140
// how many milliseonds have elapsed since we last checked?
141
unsigned long next_time = millis();
142
unsigned long delta = next_time - last_time + carry;
144
// update the previous time and carried-over milliseconds
145
last_time = next_time;
146
carry = delta % 1000;
148
// add the seconds that have passed to the time
149
time_seconds += delta / 1000;
150
while( time_seconds >= 60 ) {
153
if( time_minutes >= 60 ) {
156
if( time_hours >= 24 )
51
// ISR to handle the pulses from the fan's tachiometer
52
void fanPulseHandler()
54
// the fan actually sends two pulses per revolution. These pulses
55
// may not be exactly evenly distributed around the rotation, so
56
// we can't recalculate times on every pulse. Instead, we ignore
57
// every other pulse so timings are based on a complete rotation.
58
static bool ignore = true;
62
// set a new pulse time
63
new_pulse_at = micros();
163
// draw a segment for the test display
164
void drawNextSegment_test( bool reset )
68
// draw a particular segment
69
void drawNextSegment( bool reset )
166
// keep track of segment
167
71
static unsigned int segment = 0;
168
72
if( reset ) segment = 0;
171
// turn on inside and outside LEDs
172
digitalWrite( 4, HIGH );
173
digitalWrite( 13, HIGH );
175
// display segment number in binary across in the inside LEDs,
176
// with the LED on pin 12 showing the least-significant bit
177
for( int a = 0; a < 8; a++ )
178
digitalWrite( 12 - a, ( ( segment >> a ) & 1 )? HIGH : LOW );
182
// draw a segment for the time display
183
void drawNextSegment_time( bool reset )
185
static unsigned int second = 0;
186
static unsigned int segment = 0;
188
// handle display reset
194
// what needs to be drawn?
195
bool draw_tick = !segment && second % 5 == 0;
196
bool draw_second = !segment && second == time_seconds;
197
bool draw_minute = !segment && second == time_minutes;
198
bool draw_hour = !segment && second == time_hours;
201
digitalWrite( 13, HIGH );
202
digitalWrite( 12, draw_tick || draw_minute );
203
for( int a = 10; a <= 11; a++ )
204
digitalWrite( a, draw_minute || draw_second );
205
for( int a = 4; a <= 9; a++ )
206
digitalWrite( 10, draw_minute | draw_second || draw_hour );
209
if( ++segment >= NUM_SECOND_SEGMENTS ) {
216
// draw a display segment
217
void drawNextSegment( bool reset )
219
static int draw_mode = 0;
221
// handle mode switch requests
222
if( reset && inc_draw_mode ) {
223
inc_draw_mode = false;
230
switch( draw_mode ) {
231
case 0: drawNextSegment_test( reset ); break;
232
case 1: drawNextSegment_time( reset ); break;
75
for( int a = 0; a < 10; a++ )
76
digitalWrite( a + 4, ( ( segment >> a ) & 1 )? HIGH : LOW );