Display timer in hundredth of a second when under a minute - c++

Question

So in my current RTOS code for mbed I have a timer that counts down from 3 minutes displayed in the format of minutes:seconds.I need to implement way so when the time gets to under a minute, the time is displayed in hundredths of a second, such as 59:59. How would I do that?
Here is my current code (the relevant code for displaying time is under void lcd_func (void const *args)):
#include "mbed.h"
#include "cmsis_os.h"
#include "scoreboard.h"
#define deb 180
C12832 lcd(p5, p7, p6, p8, p11);
LM75B sensor(p28,p27);
InterruptIn By1(p15); // Up on the Joystick
InterruptIn By2(p16); // Right on the Joystick
InterruptIn By3(p12); // Down on the Joystick
InterruptIn Team(p14); // Push on the Joystick
InterruptIn Play(p13); // Left to activate clock
// declaration of IDs handle for various threads
osThreadId score_ID, LCD_ID, time_ID, temp_ID;
// definition of the thread
osThreadDef(score_func, osPriorityNormal, DEFAULT_STACK_SIZE);
osThreadDef(lcd_func, osPriorityNormal, DEFAULT_STACK_SIZE);
osThreadDef(time_func, osPriorityNormal, DEFAULT_STACK_SIZE);
osThreadDef(temp_func, osPriorityNormal, DEFAULT_STACK_SIZE);
// message from ISrs
osMessageQDef(queue, 1, uint32_t);
osMessageQId(queue_ID);
// service routines for Joystick Up, Right and Down
void By1_isr() {osMessagePut(queue_ID, 1, 0);}
void By2_isr() {osMessagePut(queue_ID, 2, 0);}
void By3_isr() {osMessagePut(queue_ID, 3, 0);}
void Team_isr();
void Time_isr();
Timer t;
int minutes,seconds,zero,faults;
int main()
{
t.start();//start the timer
By1.rise(&By1_isr);
By2.rise(&By2_isr);
By3.rise(&By3_isr);
Team.rise(&Team_isr);
Play.rise(&Time_isr);
queue_ID = osMessageCreate(osMessageQ(queue), NULL);
score_ID = osThreadCreate(osThread(score_func), NULL);
LCD_ID = osThreadCreate(osThread(lcd_func), NULL);
time_ID = osThreadCreate(osThread(time_func), NULL);
temp_ID = osThreadCreate(osThread(temp_func), NULL);
}
void Team_isr()
{
if(t.read_ms() > deb) {
score.h0v1 = !score.h0v1;
osSignalSet(LCD_ID, 0x2);
t.reset();
}
}
void Time_isr()
{
if (score.running == 0)
{
score.running = 1;
}
else
{
faults++;
score.running = 0;
}
osSignalSet(time_ID, 0x3);
}
void Timer1_Update (void const *args)
{
score.time_count -= 1;
osSignalSet(LCD_ID, 0x2);
}
void Destroy(float val)
{
osThreadTerminate(time_ID);
osThreadTerminate(score_ID);
osThreadTerminate(LCD_ID);
lcd.cls();
lcd.locate(0,3);
lcd.printf("Gamed Terminated!\n");
lcd.printf("(temperature reached %2.1f)\n", val);
osThreadTerminate(temp_ID);
}
void score_func (void const *args)
{
score.h0v1 = 0; // home by default
score.time_count = 180;
score.home_count = 0;
score.visitors_count = 0;
uint32_t val;
while (1) {
osEvent score_sig = osMessageGet(queue_ID, osWaitForever);
if (score_sig.status == osEventMessage)
val = score_sig.value.v;
if (score.h0v1 == 0)
score.home_count += val;
else
score.visitors_count += val;
osSignalSet(LCD_ID, 0x2);
}
}
void lcd_func (void const *args)
{
while(1) {
minutes=score.time_count/60;
seconds=score.time_count%60;
if (seconds<10)
{
lcd.cls();
lcd.locate(0,3);
lcd.printf("Time remaining: %2d:%d%d\n",minutes,zero,seconds);
}
else{
lcd.cls();
lcd.locate(0,3);
lcd.printf("Time remaining: %2d:%2d\n",minutes,seconds);}
if (score.h0v1 == 0)
lcd.printf("*Home: %2d Visitors: %2d\n",
score.home_count, score.visitors_count);
else
lcd.printf(" Home: %2d *Visitors: %2d\n",
score.home_count, score.visitors_count);
osSignalWait(0x2, osWaitForever);
}
}
void time_func (void const *args)
{
osTimerDef (Timer1, Timer1_Update);
osTimerId Timer1_ID;
// Activate time
Timer1_ID = osTimerCreate (osTimer(Timer1), osTimerPeriodic, NULL);
while(1) {
osSignalWait(0x3, osWaitForever);
if (score.running == 0)
osTimerStop (Timer1_ID);
else
osTimerStart (Timer1_ID, 1000UL);
}
}
void temp_func (void const *args)
{
float temp;
if (sensor.open()) {
sensor.alertTemp(40.0);
while (1) {
temp = (float)sensor.temp();
if (temp > 30.0)
Destroy(temp);
osDelay(5000);
}
}
else
osThreadTerminate(temp_ID);
}

Answer 1

Change your timer to decrement every 100th and start at 18000. Then:
minutes = score.time_count / 6000;
seconds = (score.time_count % 6000) / 100 ;
hundredths = score.time_count % 100 ;
...
if( minutes == 0 )
{
lcd.printf( "Time remaining: 00:%2d:%2d\n", seconds, hundredths ) ;
}
else
{
lcd.printf( "Time remaining: %2d:%2d:00\n", minutes, seconds ) ;
}