Mike Moore
RTOS homework 4
Diff: main.cpp
- Revision:
- 0:1013288b8e43
- Child:
- 1:5f41e2df0e85
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sun Aug 18 14:45:13 2013 +0000
@@ -0,0 +1,197 @@
+/*----------------------------------------------//------------------------------
+ student : m-moore
+ class : rtos
+ directory : RTOS_HW_03 part 1
+ file : main.cpp
+----description---------------------------------//------------------------------
+ Joystick-Controlled Metronome
+
+ features:
+ 1. post-initialization functionality all timer-driven.
+ 2. IRSs contain no blocking functions.
+ 3. LED shows the metronome beat.
+ 4. metronome speed controlled with up/down joystick.
+ 5. rate-of-speed-change depends on how long the up/down has been active.
+ 6. Beat-Per-Minute (BPM) shown on LCD display.
+
+ controls:
+ 1. joystick-up - increase metronome rate.
+ 2. joystick-down - decrease metronome rate.
+ 3. joystick-center - set metronome to 60BPM.
+
+ notes:
+
+ testing:
+ 1. confirm ease of being able to adjust one BPM rate with joystick up/down.
+ 2. confirm three joystick up/down change rates, if keeping the stick pressed.
+ 3. confirm max/min BPS saturation & display.
+ 4. confirm joystick up/down control works to change display & LED BPM.
+ 5. confirm joystick center-press sets rate to 60BPM immediately.
+ 6. confirm long-test does not result in a crash.
+ -> all items confirmed.
+
+-----includes-----------------------------------//----------------------------*/
+ #include "mbed.h" // mbed class.
+ #include "C12832_lcd.h" // LCD class.
+//---defines------------------------------------//------------------------------
+ #define LCD1 lcd.locate(0, 0); // LCD line 1.
+ #define LCD2 lcd.locate(0,11); // LCD line 2.
+ #define LCD3 lcd.locate(0,22); // LCD line 3.
+
+ #define METROMAX 800 // max. beats per minute.
+ #define METROMIN 8 // min. beats per minute.
+ #define UDSAMPLERATE 0.1 // how often to sample U/D joystick.
+ #define LCDSAMPLERATE 0.1 // how often to redraw the LCD.
+ #define PULSELENGTH 0.0625 // how long the LED-on-time is.
+//--global_definitions--------------------------//------------------------------
+//--global_variables----------------------------//------------------------------
+ float fMetroDelay; // time between ticks, in seconds.
+ float fMetroDuty; // duration of metro high, in seconds.
+ int dMetroBPM; // master parameter.
+ long lUpDownHowMany; // count how long up/down joystick pressed.
+//--global_instances----------------------------//------------------------------
+ C12832_LCD lcd; // LCD object.
+
+ DigitalIn joyStickUp (p15); // 1 if joystick up pressed.
+ DigitalIn joyStickDown (p12); // 1 if joystick down pressed.
+ DigitalIn joyStickCenter(p14); // 1 if joystick middle pressed.
+
+ DigitalOut led3(LED1); // leftmost LED.
+
+ Ticker tickerMetronome; // blinking LED.
+ Ticker tickerJoystickUD; // joystick up/down sample.
+ Ticker tickerLCD; // display ticker.
+ Timeout timeoutDutyCycle; // LED duty cycle delay.
+//-------prototypes-----------------------------//------------------------------
+ void initialization(); // initialize settings.
+ void lcd_display(); // display on LCD.
+ void interrupt_service_M(); // metronome tick.
+ void interrupt_service_UD(); // joystick up/down sample.
+ void led3_off(); // attachable LED control.
+ void led3_on(); // attachable LED control.
+//==============================================//==============================
+ int main(void)
+ {
+ initialization(); // initialize settings.
+
+ // metronome ticker.
+ tickerMetronome.attach(&interrupt_service_M,fMetroDelay);
+
+ // LCD ticker.
+ tickerLCD.attach(&lcd_display,LCDSAMPLERATE);
+
+ // up/down joystick sampling.
+ tickerJoystickUD.attach(&interrupt_service_UD,UDSAMPLERATE);
+
+ while (1) // main loop.
+ {
+ wait(10.0); // it's all interrupt-driven.
+ }
+ }
+/*----------------------------------------------//----------------------------*/
+ void initialization(void) // program initializations.
+ {
+ dMetroBPM = 60; // initialize to 60BPM.
+ fMetroDelay = 60.0 / (float) (dMetroBPM);
+ fMetroDuty = PULSELENGTH; // initialize LED on-duration.
+ lUpDownHowMany = 0;
+ }
+/*----------------------------------------------//----------------------------*/
+ void lcd_display(void) // display metronome info.
+ {
+ lcd.cls(); // clear display.
+
+ LCD1; // line 1.
+ lcd.printf(" METRONOME");
+
+ LCD2; // line 2.
+
+ if (dMetroBPM == METROMIN) // BPM, with saturation notification.
+ lcd.printf(" %5.2d BPM minimum",dMetroBPM);
+ else
+ if (dMetroBPM == METROMAX)
+ lcd.printf(" %5.2d BPM maximum",dMetroBPM);
+ else
+ lcd.printf(" %5.2d BPM",dMetroBPM);
+
+ LCD3; // line 3.
+
+ lcd.printf(" RTOS HW 3 PART 1");
+ }
+/*----------------------------------------------//----------------------------*/
+// this metronome tick ISR will self-adjust to the current user-selected
+// metronome rate. that has to be done here, and at the start of the function,
+// in order to maintain a constant phase and to prevent a beat-skip.
+
+ void interrupt_service_M() // metronome tick.
+ {
+ tickerMetronome.detach(); // only one attachment.
+ tickerMetronome.attach(&interrupt_service_M,fMetroDelay);
+ led3 = 1;
+ timeoutDutyCycle.attach(&led3_off,fMetroDuty);
+ }
+/*----------------------------------------------//----------------------------*/
+// this routine measures the number of seconds for which the joystick is
+// in the up or down position. for three ranges of time, three different
+// BPM rates-of-change are used. This means that as the user controls the
+// metronome rate using the joystick, at first it will change slowly, then
+// it will change at a moderate speed, then it will change quickly.
+// additionally, pressing the center joystick button will bring the metronome
+// back to 60BPM immediately, breaking BPM phase continuity.
+ void interrupt_service_UD(void) // joystick up/down sample
+ {
+ int dPressedSeconds; // how many seconds joystick pressed.
+ int dMultiCount; // slow count rate.
+ char cDiscontinuity; // 1 = break phase & change BPM now.
+
+ cDiscontinuity = 0; // don't break phase.
+
+ // calculate slow rate period.
+ dMultiCount = (int) ((float) (1.0 / ((float) UDSAMPLERATE)));
+
+ if (joyStickUp) // joystick up.
+ {
+ // rate-range calculations.
+ dPressedSeconds = (int) (((float) lUpDownHowMany) * UDSAMPLERATE);
+ if (dPressedSeconds < 5) {if (!(lUpDownHowMany % dMultiCount)) dMetroBPM ++;}
+ else
+ if (dPressedSeconds < 10) dMetroBPM++;
+ else dMetroBPM += 5;
+ lUpDownHowMany++; // joystick holddown time.
+ }
+ else
+ if (joyStickDown) // joystick down.
+ {
+ // rate-range calculations.
+ dPressedSeconds = (int) (((float) lUpDownHowMany) * UDSAMPLERATE);
+ if (dPressedSeconds < 5) {if (!(lUpDownHowMany % dMultiCount)) dMetroBPM --;}
+ else
+ if (dPressedSeconds < 10) dMetroBPM--;
+ else dMetroBPM -= 5;
+ lUpDownHowMany++; // joystick holddown time.
+ }
+ else lUpDownHowMany = 0; // clear when not up or down.
+
+ if (joyStickCenter)
+ {
+ dMetroBPM = 60; // center-button -> 60BPM.
+ cDiscontinuity = 1; // pending phase-break.
+ }
+ // saturate metronome BPM.
+ if (dMetroBPM > METROMAX) dMetroBPM = METROMAX;
+ if (dMetroBPM < METROMIN) dMetroBPM = METROMIN;
+
+ fMetroDelay = 60.0 / (float) (dMetroBPM); // calculate Ticker delay time.
+
+ if (cDiscontinuity) // implement 60BPS now.
+ {
+ tickerMetronome.detach(); // only one attachment.
+ tickerMetronome.attach(&interrupt_service_M,fMetroDelay);
+ }
+
+ }
+/*----------------------------------------------//----------------------------*/
+ void led3_off(void) {led3 = 0;} // turn off the LED.
+/*----------------------------------------------//----------------------------*/
+ void led3_on( void) {led3 = 1;} // turn on the led.
+/*----------------------------------------------//----------------------------*/
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