Joystick ile Kısık Işık

1#include <stdint.h>
2#include <stdbool.h>
3#include "inc/hw_memmap.h"
4#include "driverlib/sysctl.h"
5#include "driverlib/gpio.h"
6#include "driverlib/adc.h"
7 
8#define LED_ALL (GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3)
9#define PWM_STEPS 256
10 
11// Software PWM: show the color for 'periods' cycles
12static void showColor(uint8_t r, uint8_t g, uint8_t b, uint32_t periods) {
13    volatile uint32_t p, i;
14    for (p = 0; p < periods; p++)
15        for (i = 0; i < PWM_STEPS; i++) {
16            uint8_t out = 0;
17            if (i < r) out |= GPIO_PIN_1;
18            if (i < g) out |= GPIO_PIN_3;
19            if (i < b) out |= GPIO_PIN_2;
20            GPIOPinWrite(GPIO_PORTF_BASE, LED_ALL, out);
21            SysCtlDelay(2);
22        }
23}
24 
25// Read joystick X axis (PE3 / AIN0) -> 0..4095
26static uint32_t readAxis(void) {
27    uint32_t buf[1];
28    ADCProcessorTrigger(ADC0_BASE, 1);
29    while (!ADCIntStatus(ADC0_BASE, 1, false)) {}
30    ADCIntClear(ADC0_BASE, 1);
31    ADCSequenceDataGet(ADC0_BASE, 1, buf);
32    return buf[0];
33}
34 
35int main(void) {
36    SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_PLL |
37                   SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
38 
39    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
40    while (!SysCtlPeripheralReady(SYSCTL_PERIPH_GPIOF)) {}
41    GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, LED_ALL);
42 
43    SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0);
44    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
45    while (!SysCtlPeripheralReady(SYSCTL_PERIPH_ADC0)) {}
46    GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_3);          // PE3 = AIN0
47 
48    ADCSequenceConfigure(ADC0_BASE, 1, ADC_TRIGGER_PROCESSOR, 0);
49    ADCSequenceStepConfigure(ADC0_BASE, 1, 0,
50                             ADC_CTL_CH0 | ADC_CTL_IE | ADC_CTL_END);
51    ADCSequenceEnable(ADC0_BASE, 1);
52    ADCIntClear(ADC0_BASE, 1);
53 
54    while (1) {
55        uint8_t bri = (uint8_t)(readAxis() / 16);        // 0..255
56        showColor(bri, bri, bri, 20);                    // white at that brightness
57    }
58}