POSSIBILITY OF SUCH DAMAGE.
*/
+/*
+ * PS/2 protocol busywait version
+ */
+
#include <stdbool.h>
#include <util/delay.h>
#include "ps2.h"
#include "debug.h"
-/*
- * PS/2 protocol busywait version
- */
-
#define WAIT(stat, us, err) do { \
if (!wait_##stat(us)) { \
ps2_error = err; \
} \
} while (0)
+
uint8_t ps2_error = PS2_ERR_NONE;
uint8_t ps2_host_send(uint8_t data)
{
- uint8_t res = 0;
bool parity = true;
ps2_error = PS2_ERR_NONE;
+
/* terminate a transmission if we have */
inhibit();
- _delay_us(200); // at least 100us
+ _delay_us(100); // 100us [4]p.13, [5]p.50
- /* start bit [1] */
+ /* 'Request to Send' and Start bit */
data_lo();
clock_hi();
- WAIT(clock_lo, 20000, 10); // may take 15ms at most until device starts clocking
- /* data [2-9] */
+ WAIT(clock_lo, 10000, 10); // 10ms [5]p.50
+
+ /* Data bit */
for (uint8_t i = 0; i < 8; i++) {
_delay_us(15);
if (data&(1<<i)) {
WAIT(clock_hi, 50, 2);
WAIT(clock_lo, 50, 3);
}
- /* parity [10] */
+
+ /* Parity bit */
_delay_us(15);
if (parity) { data_hi(); } else { data_lo(); }
WAIT(clock_hi, 50, 4);
WAIT(clock_lo, 50, 5);
- /* stop bit [11] */
+
+ /* Stop bit */
_delay_us(15);
data_hi();
- /* ack [12] */
+
+ /* Ack */
WAIT(data_lo, 50, 6);
WAIT(clock_lo, 50, 7);
WAIT(data_hi, 50, 9);
inhibit();
- res = ps2_host_recv_response();
+ return ps2_host_recv_response();
ERROR:
inhibit();
- return res;
+ return 0;
}
/* receive data when host want else inhibit communication */
uint8_t ps2_host_recv_response(void)
{
- // Command might take 20ms to response([3]p.21)
- // TrackPoint might take 25ms ([5]2.7)
+ // Command may take 25ms/20ms at most([5]p.46, [3]p.21)
// 250 * 100us(wait for start bit in ps2_host_recv)
uint8_t data = 0;
uint8_t try = 250;
return data;
}
-/* send LED state to keyboard */
-void ps2_host_set_led(uint8_t led)
-{
- ps2_host_send(0xED);
- ps2_host_send(led);
-}
-
-
/* called after start bit comes */
uint8_t ps2_host_recv(void)
{
inhibit();
return 0;
}
+
+/* send LED state to keyboard */
+void ps2_host_set_led(uint8_t led)
+{
+ ps2_host_send(0xED);
+ ps2_host_send(led);
+}
POSSIBILITY OF SUCH DAMAGE.
*/
+/*
+ * PS/2 protocol Pin interrupt version
+ */
+
#include <stdbool.h>
-#include <avr/io.h>
-#include <avr/interrupt.h>
#include <util/delay.h>
#include "ps2.h"
#include "debug.h"
-#ifndef PS2_USE_INT
-static uint8_t recv_data(void);
-#endif
-static inline void clock_lo(void);
-static inline void clock_hi(void);
-static inline bool clock_in(void);
-static inline void data_lo(void);
-static inline void data_hi(void);
-static inline bool data_in(void);
-static inline uint16_t wait_clock_lo(uint16_t us);
-static inline uint16_t wait_clock_hi(uint16_t us);
-static inline uint16_t wait_data_lo(uint16_t us);
-static inline uint16_t wait_data_hi(uint16_t us);
-static inline void idle(void);
-static inline void inhibit(void);
-
-
-/*
-Primitive PS/2 Library for AVR
-==============================
-Host side is only supported now.
-
-
-I/O control
------------
-High state is asserted by input with pull up.
-
-
-PS/2 References
----------------
-http://www.computer-engineering.org/ps2protocol/
-http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
-*/
-
-
#define WAIT(stat, us, err) do { \
if (!wait_##stat(us)) { \
ps2_error = err; \
uint8_t ps2_error = PS2_ERR_NONE;
+static inline uint8_t pbuf_dequeue(void);
+static inline void pbuf_enqueue(uint8_t data);
+static inline bool pbuf_has_data(void);
+static inline void pbuf_clear(void);
+
+
void ps2_host_init(void)
{
- // POR(150-2000ms) plus BAT(300-500ms) may take 2.5sec([3]p.20)
- _delay_ms(2500);
-
-#ifdef PS2_USE_INT
+ idle();
PS2_INT_INIT();
PS2_INT_ON();
- idle();
-#else
- inhibit();
-#endif
+ // POR(150-2000ms) plus BAT(300-500ms) may take 2.5sec([3]p.20)
+ //_delay_ms(2500);
}
-// TODO: send using interrupt if available
uint8_t ps2_host_send(uint8_t data)
{
- uint8_t res = 0;
bool parity = true;
ps2_error = PS2_ERR_NONE;
-#ifdef PS2_USE_INT
+
PS2_INT_OFF();
-#endif
+
/* terminate a transmission if we have */
inhibit();
- _delay_us(200); // at least 100us
+ _delay_us(100); // 100us [4]p.13, [5]p.50
- /* start bit [1] */
+ /* 'Request to Send' and Start bit */
data_lo();
clock_hi();
- WAIT(clock_lo, 20000, 10); // may take 15ms at most until device starts clocking
- /* data [2-9] */
+ WAIT(clock_lo, 10000, 10); // 10ms [5]p.50
+
+ /* Data bit[2-9] */
for (uint8_t i = 0; i < 8; i++) {
_delay_us(15);
if (data&(1<<i)) {
WAIT(clock_hi, 50, 2);
WAIT(clock_lo, 50, 3);
}
- /* parity [10] */
+
+ /* Parity bit */
_delay_us(15);
if (parity) { data_hi(); } else { data_lo(); }
WAIT(clock_hi, 50, 4);
WAIT(clock_lo, 50, 5);
- /* stop bit [11] */
+
+ /* Stop bit */
_delay_us(15);
data_hi();
- /* ack [12] */
+
+ /* Ack */
WAIT(data_lo, 50, 6);
WAIT(clock_lo, 50, 7);
WAIT(clock_hi, 50, 8);
WAIT(data_hi, 50, 9);
-#ifdef PS2_USE_INT
+ idle();
PS2_INT_ON();
-#endif
- res = ps2_host_recv_response();
+ return ps2_host_recv_response();
ERROR:
-#ifdef PS2_USE_INT
- PS2_INT_ON();
idle();
-#else
- inhibit();
-#endif
- return res;
+ PS2_INT_ON();
+ return 0;
}
-#ifndef PS2_USE_INT
-/* receive data when host want else inhibit communication */
uint8_t ps2_host_recv_response(void)
{
- // Command might take 20ms to response([3]p.21)
- // TrackPoint might take 25ms ([5]2.7)
- uint8_t data = 0;
- uint8_t try = 200;
- while (try-- && (data = ps2_host_recv())) ;
- return data;
-}
-#endif
-
-#ifndef PS2_USE_INT
-uint8_t ps2_host_recv(void)
-{
- uint8_t data = 0;
-
- /* release lines(idle state) */
- idle();
-
- /* wait start bit */
- wait_clock_lo(100); // TODO: this is enough?
- data = recv_data();
-
- inhibit();
- return data;
-}
-#else
-/* ring buffer to store ps/2 key data */
-#define PBUF_SIZE 32
-static uint8_t pbuf[PBUF_SIZE];
-static uint8_t pbuf_head = 0;
-static uint8_t pbuf_tail = 0;
-static inline void pbuf_enqueue(uint8_t data)
-{
- uint8_t sreg = SREG;
- cli();
- uint8_t next = (pbuf_head + 1) % PBUF_SIZE;
- if (next != pbuf_tail) {
- pbuf[pbuf_head] = data;
- pbuf_head = next;
- } else {
- debug("pbuf: full\n");
+ // Command may take 25ms/20ms at most([5]p.46, [3]p.21)
+ uint8_t retry = 25;
+ while (retry-- && !pbuf_has_data()) {
+ _delay_ms(1);
}
- SREG = sreg;
-}
-static inline uint8_t pbuf_dequeue(void)
-{
- uint8_t val = 0;
-
- uint8_t sreg = SREG;
- cli();
- if (pbuf_head != pbuf_tail) {
- val = pbuf[pbuf_tail];
- pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE;
- }
- SREG = sreg;
-
- return val;
-}
-static inline bool pbuf_has_data(void)
-{
- uint8_t sreg = SREG;
- cli();
- bool has_data = (pbuf_head != pbuf_tail);
- SREG = sreg;
- return has_data;
-}
-static inline void pbuf_clear(void)
-{
- uint8_t sreg = SREG;
- cli();
- pbuf_head = pbuf_tail = 0;
- SREG = sreg;
+ return pbuf_dequeue();
}
/* get data received by interrupt */
uint8_t ps2_host_recv(void)
{
- return pbuf_dequeue();
-}
-
-uint8_t ps2_host_recv_response(void)
-{
- while (!pbuf_has_data()) ;
- return pbuf_dequeue();
+ if (pbuf_has_data()) {
+ ps2_error = PS2_ERR_NONE;
+ return pbuf_dequeue();
+ } else {
+ ps2_error = PS2_ERR_NODATA;
+ return 0;
+ }
}
ISR(PS2_INT_VECT)
if (!data_in())
goto ERROR;
pbuf_enqueue(data);
-//phex(data);
goto DONE;
break;
default:
}
goto RETURN;
ERROR:
- inhibit();
ps2_error = state;
DONE:
state = INIT;
RETURN:
return;
}
-#endif
-
/* send LED state to keyboard */
void ps2_host_set_led(uint8_t led)
}
-#ifndef PS2_USE_INT
-/* called after start bit comes */
-static uint8_t recv_data(void)
+/*--------------------------------------------------------------------
+ * Ring buffer to store scan codes from keyboard
+ *------------------------------------------------------------------*/
+#define PBUF_SIZE 32
+static uint8_t pbuf[PBUF_SIZE];
+static uint8_t pbuf_head = 0;
+static uint8_t pbuf_tail = 0;
+static inline void pbuf_enqueue(uint8_t data)
{
- uint8_t data = 0;
- bool parity = true;
- ps2_error = PS2_ERR_NONE;
-
- /* start bit [1] */
- WAIT(clock_lo, 1, 1);
- WAIT(data_lo, 1, 2);
- WAIT(clock_hi, 50, 3);
-
- /* data [2-9] */
- for (uint8_t i = 0; i < 8; i++) {
- WAIT(clock_lo, 50, 4);
- if (data_in()) {
- parity = !parity;
- data |= (1<<i);
- }
- WAIT(clock_hi, 50, 5);
- }
-
- /* parity [10] */
- WAIT(clock_lo, 50, 6);
- if (data_in() != parity) {
- ps2_error = PS2_ERR_PARITY;
- goto ERROR;
+ uint8_t sreg = SREG;
+ cli();
+ uint8_t next = (pbuf_head + 1) % PBUF_SIZE;
+ if (next != pbuf_tail) {
+ pbuf[pbuf_head] = data;
+ pbuf_head = next;
+ } else {
+ debug("pbuf: full\n");
}
- WAIT(clock_hi, 50, 7);
-
- /* stop bit [11] */
- WAIT(clock_lo, 50, 8);
- WAIT(data_hi, 1, 9);
- WAIT(clock_hi, 50, 10);
-
- return data;
-ERROR:
- return 0;
-}
-#endif
-
-static inline void clock_lo()
-{
- PS2_CLOCK_PORT &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_DDR |= (1<<PS2_CLOCK_BIT);
-}
-static inline void clock_hi()
-{
- /* input with pull up */
- PS2_CLOCK_DDR &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_PORT |= (1<<PS2_CLOCK_BIT);
-}
-static inline bool clock_in()
-{
- PS2_CLOCK_DDR &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_PORT |= (1<<PS2_CLOCK_BIT);
- _delay_us(1);
- return PS2_CLOCK_PIN&(1<<PS2_CLOCK_BIT);
-}
-static inline void data_lo()
-{
- PS2_DATA_PORT &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_DDR |= (1<<PS2_DATA_BIT);
-}
-static inline void data_hi()
-{
- /* input with pull up */
- PS2_DATA_DDR &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_PORT |= (1<<PS2_DATA_BIT);
+ SREG = sreg;
}
-static inline bool data_in()
+static inline uint8_t pbuf_dequeue(void)
{
- PS2_DATA_DDR &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_PORT |= (1<<PS2_DATA_BIT);
- _delay_us(1);
- return PS2_DATA_PIN&(1<<PS2_DATA_BIT);
-}
+ uint8_t val = 0;
-static inline uint16_t wait_clock_lo(uint16_t us)
-{
- while (clock_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_clock_hi(uint16_t us)
-{
- while (!clock_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_data_lo(uint16_t us)
-{
- while (data_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_data_hi(uint16_t us)
-{
- while (!data_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
+ uint8_t sreg = SREG;
+ cli();
+ if (pbuf_head != pbuf_tail) {
+ val = pbuf[pbuf_tail];
+ pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE;
+ }
+ SREG = sreg;
-/* idle state that device can send */
-static inline void idle(void)
+ return val;
+}
+static inline bool pbuf_has_data(void)
{
- clock_hi();
- data_hi();
+ uint8_t sreg = SREG;
+ cli();
+ bool has_data = (pbuf_head != pbuf_tail);
+ SREG = sreg;
+ return has_data;
}
-
-/* inhibit device to send */
-static inline void inhibit(void)
+static inline void pbuf_clear(void)
{
- clock_lo();
- data_hi();
+ uint8_t sreg = SREG;
+ cli();
+ pbuf_head = pbuf_tail = 0;
+ SREG = sreg;
}
-
-/* PS/2 Resources
- *
- * [1] The PS/2 Mouse/Keyboard Protocol
- * http://www.computer-engineering.org/ps2protocol/
- * Concise and thorough primer of PS/2 protocol.
- *
- * [2] Keyboard and Auxiliary Device Controller
- * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
- * Signal Timing and Format
- *
- * [3] Keyboards(101- and 102-key)
- * http://www.mcamafia.de/pdf/ibm_hitrc11.pdf
- * Keyboard Layout, Scan Code Set, POR, and Commands.
- *
- * [4] PS/2 Reference Manuals
- * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
- * Collection of IBM Personal System/2 documents.
- *
- * [5] TrackPoint Engineering Specifications for version 3E
- * https://web.archive.org/web/20100526161812/http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
- */
projects / max / tmk_keyboard.git / commitdiff