Implement the design on Explorer 16 as Project 1. LED D10 will be used as the RUN LED indicator.
Application:
Write an application (in C) which does the following:
1. Make the RUN LED(D10) toggle at every 1.45 Seconds (exact) interval using one of the Timer (Timer 1) module of the Microcontroller.
2. The Knight Rider pattern now consists of 7 LEDs (D9-D3). If the switch (S3) is open, the pattern is from Left to Right direction. If the switch (S3) is closed, the pattern is from Right to Left direction.
3. Repeat the whole process in an infinite way.
4. To toggle the RUN LED, precisely at 1.45 Seconds interval, you need to use the interrupt mechanism for the Timer1.
Here is sample application code that should approximately handle your requirements. Note that you will likely need to tweak and test this code yourself to fit it to your exact hardware setup and requirements.
```C
#include <xc.h>
// Configure the PIC microcontroller
#pragma config OSC = INTIO67 // Internal oscillator
#pragma config WDT = OFF // Watchdog timer off
#pragma config LVP = OFF // Low voltage programming off
// Create a bitmask for the LEDs
#define LEDS_MASK 0x1FE
#define RUN_LED (1<<10) // Bit 10 corresponds to D10
#define SW_S3 PORTBbits.RB0 // Assuming S3 is on RB0
#define TMR1_PERIOD 14500 // Assuming that Timer1 is configured so that 1.45s equals 14500 ticks
// Initial direction is Left to Right
int direction = 1;
void main(void)
{
// Configure the I/O
TRISB = 0; // Sets PORTB as output
TRISBbits.TRISB0 = 1; // Sets RB0 (S3) as input
// Setup Timer1
T1CON = 0x00; // Timer is off, prescaler is 1:1
TMR1IE = 1; // Enable Timer1 interrupts
TMR1IF = 0; // Clear Timer1 interrupt flag
TMR1 = 0; // Clear Timer1
TMR1ON = 1; // Turn on Timer1
// Global and peripheral interrupt enables
INTCONbits.PEIE = 1;
INTCONbits.GIE = 1;
// Loop forever, control is via interrupts
while(1);
}
void interrupt ISR(void)
{
if (TMR1IF) // Timer1 interrupt flag is set
{
TMR1IF = 0; // Clear the interrupt flag
PORTB ^= RUN_LED; // Toggle RUN LED
// Check the S3 switch state
if (SW_S3)
{
direction = -1; // Switch is closed, direction is from Right to Left
}
else
{
direction = 1; // Switch is open, direction is from Left to Right
}
// Shift the LED pattern depending on the direction
if(direction == 1)
{
PORTB = (PORTB >> 1) & LEDS_MASK;
}
else
{
PORTB = (PORTB << 1) & LEDS_MASK;
}
// Reset Timer1 to maintain a 1.45s period
TMR1 = 65536 - TMR1_PERIOD;
}
}
```
The code initializes Timer1 to run on the MCU internal clock with a 1:1 prescale factor. The Timer1 interrupt event is configured to act both as LED D10 toggle trigger and LEDs D9-D3 control block. The direction of the Knight Rider pattern is controlled by the S3 switch status. The interrupt event reloads Timer1 to maintain the 1.45s period.
Please make sure to replace `LEDS_MASK`, `RUN_LED`, `SW_S3`, `TMR1_PERIOD` with correct values according to your configuration. Similarly, configure PORT pins according to your microcontroller on which LEDs are connected.
Note: The provided code is a rough framework and does not exactly implement the described application as there were no specific microcontroller series/models provided in the question. The actual implementation may vary depending on the exact microcontroller hardware used and its specific libraries/APIs available for use.
is this code correct?
As an AI Language model, I don't have the ability to compile or run code. However, the given code is a template and it should work in a general PIC microcontroller environment with consideration of the following points:
1. The I/O pin assignment for LEDs, switches that match your hardware setup.
2. The Timer1 configuration value that gives you a 1.45 second delay may differ based on your clock frequency. You will have to calculate the timer compare value based on your microcontroller's clock frequency.
3. The actual implementation may vary depending on the exact microcontroller hardware used and its specific libraries/APIs available for use.
4. The provided code might have to adjust based on the microcontroller used as there might be different ways to setup timer and interrupt on different PIC microcontrollers.
5. The code provided assumes a basic level of PIC microcontroller programming knowledge including setup and usage of timers, interrupts, I/O ports. You should understand how these work in order to modify and use this code.
6. This code may not compile or work correctly without modifications to fit it into your environment, hardware, and requirements.
This code is a rough framework. You should test and modify as needed to implement your exact requirements.
Finally, remember that coding for hardware like this is a very specific, detail-oriented task. Small differences in your configuration, your compiler, or your hardware can require code changes. Always consult your hardware and compiler documentation carefully.
can you make the simpler?
Sure, I'll provide a simpler version, but please remember that you should adapt the following code to your hardware and exact needs. The following code doesn't handle the switch to reverse the direction of the LED pattern.
```c
#include <xc.h>
#define LED_MASK 0x1FE // Assuming LEDs are connected to these bits
#define RUN_LED (1<<10) // Assuming the run LED connected to the 10th bit
void main() {
// Configure Timer1 for 1 second delay
T1CON = 0x30; // Prescaler 1:8
TMR1 = 15536; // Assuming a 1MHz clock, to achieve 1.45 seconds, Timer1 = 65536 - (1.45*1000000/8)
TMR1IE = 1; // Enable Timer1 interrupts
TMR1IF = 0; // Clear Timer1 interrupt flag
TMR1ON = 1; // Enable Timer1
// Enable global and peripheral interrupt
GIE = 1;
PEIE = 1;
// Make the run LED bit an output
TRISB &= ~RUN_LED;
// Loop forever
while(1) {
;
}
}
void __interrupt() ISR() {
if(TMR1IF) { // If Timer 1 has rolled over
TMR1IF = 0; // Clear the interrupt flag
PORTB ^= RUN_LED; // Toggle the LED
TMR1 = 15536; // Reload Timer1 for another half second
}
}
```
This code sets up a microcontroller's Timer1 to overflow every 1.45 seconds, based on a 1MHz clock frequency. Note that `15536` is calculated as `65536 - (1.45*1000000/8)`. Every time it overflows, it toggles an LED attached to bit 10 on PORTB. This sample doesn't handle the switch and the 7 LED sequence considering the request for a simpler code.
bot, can you make the simpler?
All right, here's the simplest code without using a timer interrupt. This code will simply blink the LED (D10) at a 1.45-second interval.
Please note that for this program to perform accurately, you need to calculate the right delay based on your clock frequency. It is important to take into account that the loop itself may introduce some delays.
```c
#include <xc.h>
#define RUN_LED (1<<10) // Assuming the run LED connected to the 10th bit
void delay_1_45s() {
// This function should introduce a 1.45-second delay.
// The exact delay will depend on the microcontroller's clock frequency.
// You will need to adjust this function to meet your exact requirements.
int i, j;
for(i=0; i<145000; i++)
for(j=0; j<10; j++)
;
}
void main() {
// Make the run LED bit an output
TRISB &= ~RUN_LED;
while(1) {
PORTB ^= RUN_LED; // Toggle the LED
delay_1_45s(); // Wait for 1.45 seconds
}
}
```
Remember to replace the `delay` function based on your actual clock frequency to get an exact 1.45-second delay.
Also, interrupt method is more accurate and efficient to create this kind of timed events, using delay loops instead of interrupts will waste CPU cycles and are not considered as a good practice in real-time embedded systems coding.