/*
-Copyright 2010,2011 Jun WAKO <wakojun@gmail.com>
+Copyright 2010,2011,2012,2013 Jun WAKO <wakojun@gmail.com>
This software is licensed with a Modified BSD License.
All of this is supposed to be Free Software, Open Source, DFSG-free,
#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);
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
PS2_INT_INIT();
PS2_INT_ON();
#endif
/* terminate a transmission if we have */
inhibit();
- _delay_us(100);
+ _delay_us(200); // at least 100us
/* start bit [1] */
data_lo();
clock_hi();
- WAIT(clock_lo, 15000, 1);
+ WAIT(clock_lo, 20000, 10); // may take 15ms at most until device starts clocking
/* data [2-9] */
for (uint8_t i = 0; i < 8; i++) {
_delay_us(15);
WAIT(clock_hi, 50, 8);
WAIT(data_hi, 50, 9);
+#ifdef PS2_USE_INT
+ PS2_INT_ON();
+#endif
res = ps2_host_recv_response();
ERROR:
#ifdef PS2_USE_INT
return res;
}
+#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
- /* terminate a transmission if we have */
- inhibit();
- _delay_us(100);
+#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(2000);
+ wait_clock_lo(100); // TODO: this is enough?
data = recv_data();
inhibit();
return data;
}
-
-#ifndef PS2_USE_INT
-uint8_t ps2_host_recv(void)
-{
- return ps2_host_recv_response();
-}
#else
/* ring buffer to store ps/2 key data */
#define PBUF_SIZE 32
static uint8_t pbuf_tail = 0;
static inline void pbuf_enqueue(uint8_t data)
{
- if (!data)
- return;
-
uint8_t sreg = SREG;
cli();
uint8_t next = (pbuf_head + 1) % PBUF_SIZE;
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;
+}
/* get data received by interrupt */
uint8_t ps2_host_recv(void)
{
- if (ps2_error) {
- print("x");
- phex(ps2_error);
- ps2_host_send(0xFE); // request to resend
- ps2_error = PS2_ERR_NONE;
- }
- idle();
return pbuf_dequeue();
}
-#if 0
-#define DEBUGP_INIT() do { DDRC = 0xFF; } while (0)
-#define DEBUGP(x) do { PORTC = x; } while (0)
-#else
-#define DEBUGP_INIT()
-#define DEBUGP(x)
-#endif
+uint8_t ps2_host_recv_response(void)
+{
+ while (!pbuf_has_data()) ;
+ return pbuf_dequeue();
+}
+
ISR(PS2_INT_VECT)
{
static enum {
}
state++;
- DEBUGP(state);
switch (state) {
case START:
if (data_in())
if (!data_in())
goto ERROR;
pbuf_enqueue(data);
+//phex(data);
goto DONE;
break;
default:
}
goto RETURN;
ERROR:
- DEBUGP(0x0F);
inhibit();
ps2_error = state;
DONE:
#endif
-static void ps2_reset(void)
-{
- ps2_host_send(0xFF);
-}
-
/* 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)
{
ERROR:
return 0;
}
+#endif
static inline void clock_lo()
{
clock_lo();
data_hi();
}
+
+
+/* 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
+ */