WebSVN – DashDisplay – Blame – /trunk/Src/switches.c

Rev	Author	Line No.	Line
2	mjames	1	#include "stm32f1xx_hal.h"
		2
		3	#include "switches.h"
		4
		5
		6	typedef enum {
		7	PH_00 = 0, PH_10 = 2, PH_11 = 3, PH_01 = 1,
		8	} eGreyCode;
		9
		10	typedef struct {
		11	GPIO_TypeDef * GPIO;
		12	uint16_t Pin;
5	mjames	13	uint16_t Debounce;
2	mjames	14	} sGPIOPin;
		15
		16	volatile int dial_pos[MAX_DIALS];
		17	volatile int dial_last[MAX_DIALS]; // previous debounced switch position
		18
		19	volatile int push_pos[MAX_PUSHBUTTONS];
		20
		21	volatile static int sw_newstate[MAX_SWITCHES]; //< debounced switch state
		22	volatile static int sw_count[MAX_SWITCHES]; //< debounce counter
		23
		24	static const sGPIOPin sw_arr[MAX_SWITCHES] =
5	mjames	25	{ { SW1_I_GPIO_Port, SW1_I_Pin , 5}, // these two pins used to encode SW1 phase
		26	{ SW1_Q_GPIO_Port, SW1_Q_Pin, 5 }, // " SW1 phase
		27	{ SW2_I_GPIO_Port, SW2_I_Pin , 5}, // these two pins used to encode SW2 phase
		28	{ SW2_Q_GPIO_Port, SW2_Q_Pin , 5}, // " SW2 phase
		29	{ SW1_PUSH_GPIO_Port, SW1_PUSH_Pin, 10 }, // two debounced switches
		30	{ SW2_PUSH_GPIO_Port, SW2_PUSH_Pin, 10 }, };
2	mjames	31
		32	// call this to setup switch states
		33	void InitSwitches(void) {
		34	int i;
		35
		36	for (i = 0; i < MAX_SWITCHES; i++) {
		37	sw_newstate[i] = 0;
		38	sw_count[i] = 0;
		39	}
		40
		41	// reset the dial positions
		42	dial_pos[0] = 0;
4	mjames	43	dial_pos[1] = 0;
2	mjames	44	}
		45
4	mjames	46	// this gray encodes the dial , but you cannot turn the switch back below 0
2	mjames	47	void EncodeDial(int i) {
		48	if (i < MAX_DIALS && i >= 0) {
		49	int sw_index = i << 1;
		50	// dial 0 uses switches 0 and 1
		51	// dial 1 uses switches 2 and 3
		52	int current = sw_newstate[sw_index] \| (sw_newstate[sw_index + 1] << 1);
		53	switch (dial_last[i]) {
		54	case PH_00:
		55	if (current == PH_10)
		56	dial_pos[i]++;
4	mjames	57	if (current == PH_01 && dial_pos[i]>0)
2	mjames	58	dial_pos[i]--;
		59	break;
		60	case PH_10:
		61	if (current == PH_11)
		62	dial_pos[i]++;
4	mjames	63	if (current == PH_00 && dial_pos[i]>0)
2	mjames	64	dial_pos[i]--;
		65	break;
		66	case PH_11:
		67	if (current == PH_01)
		68	dial_pos[i]++;
4	mjames	69	if (current == PH_10 && dial_pos[i]>0)
2	mjames	70	dial_pos[i]--;
		71	break;
		72	case PH_01:
		73	if (current == PH_00)
		74	dial_pos[i]++;
4	mjames	75	if (current == PH_11 && dial_pos[i]>0)
2	mjames	76	dial_pos[i]--;
		77	break;
		78	default:
		79	break;
		80	}
		81	dial_last[i] = current;
		82	}
		83
		84	}
		85
		86	// this is the interrupt handler , dealling with the switches
		87	void HandleSwitches(void)
		88	{
		89
		90	int i;
		91
		92	for (i = 0; i < MAX_SWITCHES; i++)
		93	{
		94
		95	int sw = HAL_GPIO_ReadPin(sw_arr[i].GPIO, sw_arr[i].Pin) == GPIO_PIN_RESET;
		96
		97	// bouncing, reset counter
4	mjames	98	if (sw == sw_newstate[i])
2	mjames	99	{
		100	sw_count[i] = 0;
		101	}
		102	else
		103	{
		104	// count up to debounce time
5	mjames	105	if (sw_count[i] < sw_arr[i].Debounce)
2	mjames	106	{
		107	sw_count[i]++;
		108
5	mjames	109	if (sw_count[i] == sw_arr[i].Debounce)
2	mjames	110	{
		111	sw_newstate[i] = sw;
		112	}
		113	}
		114	}
		115	}
		116	// we now have debounced switch states in sw_newstate . So we can go ahead and feed some of the
		117
		118	EncodeDial(0);
		119	EncodeDial(1);
		120
		121	}
		122
		123	void zero_dial(int dial) {
		124	if(dial>=0 && dial < MAX_DIALS)
		125	dial_pos[dial]= 0;
		126	}
		127

Subversion Repositories DashDisplay

(root)/trunk/Src/switches.c – Rev 5