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Question: Revise the code in “main.c” such that the program shows a running clock on the display, with ...
Revise the code in “main.c” such that the program shows a running clock on the display, with the following requirements:
1. The clock shows two digits of minutes to the left of the colon, and two digits of seconds to the right of the colon. The clock advances every second.
2. The colon (‘:’) flashes on and off every half second.
3. The user may push pushbutton SW1 to fast forward the minutes of the clock with wrap-around. Hint: You may use the pushbutton function in lab 1 as template.
4. The user may push pushbutton SW2 to fast forward the seconds of the block with wrap-around.
/*
* main.c
*
* Created on:
* Author:
*/
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <driverlib/sysctl.h>
#include <inc/hw_ints.h>
#include <inc/hw_memmap.h>
#include <inc/hw_i2c.h>
#include <driverlib/gpio.h>
#include <driverlib/pin_map.h>
#include <driverlib/i2c.h>
#include "launchpad.h"
#include "seg7.h"
// 7-segment coding table. See https://en.wikipedia.org/wiki/Seven-segment_display. The segments
// are named as A, B, C, D, E, F, G. In this coding table, segments A-G are mapped to bits 0-7.
// Bit 7 is not used in the coding. This display uses active high signal, in which '1' turns ON a
// segment, and '0' turns OFF a segment.
static uint8_t seg7Coding[10] = {
0b00111111, // digit 0
0b00000110, // digit 1
0b01011011, // digit 2
0b01001111, // digit 3
0b01100110, // digit 4
0b01101101, // digit 5
0b01111101, // digit 6
0b00000111, // digit 7
0b01111111, // digit 8
0b01101111, // digit 9
};
// The colon status: if colon == 0b10000000, then the colon is on,
// otherwise it is off.
static uint8_t colon = 0;
// Update the clock display
void
clockUpdate(uint32_t time) // pointer to a 4-byte array
{
uint8_t code[4]; // The 7-segment code for the four clock digits
// Display 01:23 on the 7-segment displays
// The colon ':' will flash on and off every 0.5 seconds
code[0] = seg7Coding[3] + colon;
code[1] = seg7Coding[2] + colon;
code[2] = seg7Coding[1] + colon;
code[3] = seg7Coding[0] + colon;
seg7Update(code);
// Calculate the display digits and colon setting for the next update
if (colon == 0b00000000) {
colon = 0b10000000;
}
else {
colon = 0b00000000;
}
// Call back after 1 second
schdCallback(clockUpdate, time + 500);
}
int main(void)
{
lpInit();
seg7Init();
uprintf("%s ", "Lab 2: Wall clock");
// Schedule the first callback events for LED flashing and push button checking.
// Those trigger callback chains. The time unit is millisecond.
schdCallback(clockUpdate, 1000);
// Loop forever
while (true) {
schdExecute();
}
}
Explanation / Answer
THE CODE HAS CHANGED
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <driverlib/sysctl.h>
#include <inc/hw_ints.h>
#include <inc/hw_memmap.h>
#include <inc/hw_i2c.h>
#include <driverlib/gpio.h>
#include <driverlib/pin_map.h>
#include <driverlib/i2c.h>
#include "launchpad.h"
#include "seg7.h"
// 7-segment coding table. See https://en.wikipedia.org/wiki/Seven-segment_display. The segments
// are named as A, B, C, D, E, F, G. In this coding table, segments A-G are mapped to bits 0-7.
// Bit 7 is not used in the coding. This display uses active high signal, in which '1' turns ON a
// segment, and '0' turns OFF a segment.
static uint8_t seg7Coding[10] = {
0b00111111, // digit 0
0b00000110, // digit 1
0b01011011, // digit 2
0b01001111, // digit 3
0b01100110, // digit 4
0b01101101, // digit 5
0b01111101, // digit 6
0b00000111, // digit 7
0b01111111, // digit 8
0b01101111, // digit 9
};
// The colon status: if colon == 0b10000000, then the colon is on,
// otherwise it is off.
static uint8_t colon = 0;
// Update the clock display
void
clockUpdate(uint32_t time) // pointer to a 4-byte array
{
uint8_t code[4]; // The 7-segment code for the four clock digits
// Display 01:23 on the 7-segment displays
// The colon ':' will flash on and off every 0.5 seconds
code[0] = seg7Coding[3] + colon;
code[1] = seg7Coding[2] + colon;
code[2] = seg7Coding[1] + colon;
code[3] = seg7Coding[0] + colon;
seg7Update(code);
// Calculate the display digits and colon setting for the next update
if (colon == 0b00000000) {
colon = 0b10000000;
}
else {
colon = 0b00000000;
}
// Call back after 1 second
schdCallback(clockUpdate, time + 500);
}
int main(void)
{
lpInit();
seg7Init();
uprintf("%s ", "Lab 2: Wall clock");
// Schedule the first callback events for LED flashing and push button checking.
// Those trigger callback chains. The time unit is millisecond.
schdCallback(clockUpdate, 1000);
// Loop forever
while (true) {
schdExecute();
}
}
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