Files
tron.asm/src/io.c
2016-01-27 14:33:51 +01:00

96 lines
2.9 KiB
C

#include "io.h"
// Local functions
typedef struct pin_s {
GPIO_TypeDef* GPIO;
uint16_t pinmask;
bool input;
} pin_t;
static void pin_create(pin_t* pin, GPIO_TypeDef* GPIO, uint8_t pinnr, bool input);
static bool pin_get(pin_t* pin);
static void pin_set(pin_t* pin, bool status);
static void pin_toggle(pin_t* pin);
// Local variables
static pin_t pin_t0;
static pin_t pin_t1;
static pin_t pin_t2;
static pin_t pin_t3;
static uint8_t new = 0;
static uint8_t old = 0;
static volatile uint8_t edg = 0;
void pin_create(pin_t* pin, GPIO_TypeDef* GPIO, uint8_t pinnr, bool input) {
GPIO_InitTypeDef gi; // Create gpio init structure
GPIO_StructInit(&gi); // Fill gpio init structure with defaults
gi.GPIO_Pin = 1 << pinnr; // create bitmask out of pin number
if(input) { // If the pin is set to be an input
gi.GPIO_Mode = GPIO_Mode_IN; // Set mode to input
gi.GPIO_OType = GPIO_OType_OD; // Set type to open drain
gi.GPIO_PuPd = GPIO_PuPd_UP; // Set a pullup
} else {
gi.GPIO_Mode = GPIO_Mode_OUT; // Set mode to output
gi.GPIO_OType = GPIO_OType_PP; // Set type to pushpull
gi.GPIO_PuPd = GPIO_PuPd_NOPULL; // Set no pullup
}
GPIO_Init(GPIO,&gi); // Update the GPIO configuration
pin->GPIO=GPIO; // Set the gpiopin in the pin structure
pin->pinmask=0x01<<pinnr; // Insert the pinmask
pin->input = input; // Store the input information
}
bool pin_get(pin_t* pin) {
if(pin->input) { // If the pin is an input
return GPIO_ReadInputDataBit(pin->GPIO,pin->pinmask); // Read its value
} else { // If the pin is an output
return GPIO_ReadOutputDataBit(pin->GPIO,pin->pinmask); // Read its set value
}
}
void pin_set(pin_t* pin, bool status) {
if(!pin->input) { // If the pin isn't an input
GPIO_WriteBit(pin->GPIO,pin->pinmask,status); // Set its value accordingly
}
}
void pin_toggle(pin_t* pin) {
if(!pin->input) { // If the pin isn't an input
pin_set(pin,!pin_get(pin)); // Toggle its value
}
}
void io_init(void){
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOC,ENABLE); // Enable gpio clock source
pin_create(&pin_t0, GPIOC, 7, true); // create pin_t0
pin_create(&pin_t1, GPIOB, 15, true); // create pin_t1
pin_create(&pin_t2, GPIOB, 14, true); // create pin_t2
pin_create(&pin_t3, GPIOI, 0, true); // create pin_t3
}
void io_process(void) {
new = pin_get(&pin_t0) |
pin_get(&pin_t1) << 1 |
pin_get(&pin_t2) << 2 |
pin_get(&pin_t3) << 3;
edg |= (new ^ old) & new; // detect positive edge
old = new;
}
bool io_button_has_edge(uint8_t btnnumber) {
uint8_t bm = (1 << btnnumber); // create bitmask
bool status = ((edg & bm) > 0); // check if button is pressed
if(status){
edg &= ~bm; // clear edge bit
}
return status;
}