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July 3, 2012 13:17
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PS/2Keyboard for Arduino Uno/Leonardo 20120703 test
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/* | |
http://arduino.cc/playground/Main/PS2Keyboard | |
http://arduino.cc/playground/Main/PS2KeyboardExt2 | |
http://msdn.microsoft.com/en-us/library/windows/hardware/gg463446.aspx | |
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
This library is free software; you can redistribute it and/or | |
modify it under the terms of the GNU Lesser General Public | |
License as published by the Free Software Foundation; either | |
version 2.1 of the License, or (at your option) any later version. | |
This library is distributed in the hope that it will be useful, | |
but WITHOUT ANY WARRANTY; without even the implied warranty of | |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
Lesser General Public License for more details. | |
You should have received a copy of the GNU Lesser General Public | |
License along with this library; if not, write to the Free Software | |
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
*/ | |
#include <avr/io.h> | |
#include <avr/interrupt.h> | |
#include <avr/pgmspace.h> | |
#include "Arduino.h" | |
#include "PS2kybd.h" | |
#include "binary.h" | |
// Scancode FIFO | |
#define BUFFER_SIZE 64 | |
static volatile uint8_t Buffer[BUFFER_SIZE]; | |
static volatile uint8_t head, tail; | |
int ps2Keyboard_DataPin; | |
volatile uint8_t ps2Keyboard_CurrentBuffer; | |
volatile uint8_t ps2Keyboard_BufferPos; | |
// variables used to remember information about key presses | |
volatile bool ps2Keyboard_shift; // indicates shift key is pressed | |
volatile bool ps2Keyboard_ctrl; // indicates the ctrl key is pressed | |
volatile bool ps2Keyboard_alt; // indicates the alt key is pressed | |
volatile bool ps2Keyboard_extend; // remembers a keyboard extended char received | |
volatile bool ps2Keyboard_release; // distinguishes key presses from releases | |
volatile bool ps2Keyboard_caps_lock; // remembers shift lock has been pressed | |
// vairables used in sending command bytes to the keyboard, eg caps_lock light | |
volatile bool cmd_in_progress; | |
volatile int cmd_count; | |
uint8_t cmd_value; | |
volatile uint8_t cmd_ack_value; | |
uint8_t cmd_parity; | |
volatile bool cmd_ack_byte_ok; | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
// subroutines | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
// odd parity | |
uint8_t odd_parity(uint8_t val) { | |
val ^= val>>4; val ^= val>>2; val ^= val>>1; | |
return (~val) & 1; | |
} | |
void v_modifier_initialize() { | |
ps2Keyboard_BufferPos = 0; | |
ps2Keyboard_shift = false; | |
ps2Keyboard_ctrl = false; | |
ps2Keyboard_alt = false; | |
ps2Keyboard_extend = false; | |
ps2Keyboard_release = false; | |
ps2Keyboard_caps_lock = false; | |
} | |
void v_initialize() { | |
v_modifier_initialize(); | |
// reset all the global variables | |
ps2Keyboard_CurrentBuffer = 0; | |
cmd_in_progress = false; | |
cmd_count = 0; | |
cmd_value = 0; | |
cmd_ack_value = 1; | |
} | |
static inline uint8_t get_scan_code(void) { | |
uint8_t c, i; | |
i = tail; | |
if (i == head) return 0; | |
i++; | |
if (i >= BUFFER_SIZE) i = 0; | |
c = Buffer[i]; | |
tail = i; | |
return c; | |
} | |
// The ISR for the external interrupt | |
void ps2interrupt(void) | |
{ | |
static uint8_t bitcount=0; | |
static uint8_t incoming=0; | |
static uint32_t prev_ms=0; | |
uint32_t now_ms; | |
uint8_t n, val; | |
val = digitalRead(ps2Keyboard_DataPin); | |
now_ms = millis(); | |
if (now_ms - prev_ms > 250) { | |
bitcount = 0; | |
incoming = 0; | |
} | |
prev_ms = now_ms; | |
n = bitcount - 1; | |
if (n <= 7) { | |
incoming |= (val << n); | |
} | |
bitcount++; | |
if (bitcount == 11) { | |
uint8_t i = head + 1; | |
if (i >= BUFFER_SIZE) i = 0; | |
if (i != tail) { | |
Buffer[i] = incoming; | |
head = i; | |
} | |
bitcount = 0; | |
incoming = 0; | |
} | |
} | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
// | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
void kbd_send_command(uint8_t val) { | |
// stop interrupt routine from receiving characters so that we can use it | |
// to send a byte | |
cmd_in_progress = true; | |
cmd_count = 0; | |
// set up the byte to shift out and initialise the ack bit | |
cmd_value = val; | |
cmd_ack_value = 1; // the kbd will clear this bit on receiving the byte | |
cmd_parity = odd_parity(val); | |
// set the data pin as an output, ready for driving | |
digitalWrite(ps2Keyboard_DataPin, HIGH); | |
pinMode(ps2Keyboard_DataPin, OUTPUT); | |
// drive clock pin low - this is going to generate the first | |
// interrupt of the shifting out process | |
pinMode(PS2_INT_PIN, OUTPUT); | |
digitalWrite(PS2_INT_PIN, LOW); | |
// wait at least one clock cycle (in case the kbd is mid transmission) | |
delayMicroseconds(60); | |
// set up the 0 start bit | |
digitalWrite(ps2Keyboard_DataPin, LOW); | |
// let go of clock - the kbd takes over driving the clock from here | |
digitalWrite(PS2_INT_PIN, HIGH); | |
pinMode(PS2_INT_PIN, INPUT); | |
// wait for interrupt routine to shift out byte, parity and receive ack bit | |
while (cmd_ack_value!=0) ; | |
// switch back to the interrupt routine receiving characters from the kbd | |
cmd_in_progress = false; | |
} | |
// val : bit_3=KANA_lock, bit_2=caps_lock, bit_1=num_lock, bit_0=scroll_lock | |
void kbd_set_lights(uint8_t val) { | |
// When setting the lights with the 0xED command the keyboard responds | |
// with an "ack byte", 0xFA. This is NOT the same as the "ack bit" that | |
// follows the succesful shifting of each command byte. See this web | |
// page for a good description of all this: | |
// http://www.beyondlogic.org/keyboard/keybrd.htm | |
cmd_ack_byte_ok = false; // initialise the ack byte flag | |
kbd_send_command(0xED); // send the command byte | |
while (!cmd_ack_byte_ok) ; // ack byte from keyboard sets this flag | |
kbd_send_command(val); // now send the data | |
} | |
// The ISR for the external interrupt | |
// This may look like a lot of code for an Interrupt routine, but the switch | |
// statements are fast and the path through the routine is only ever a few | |
// simple lines of code. | |
void ps2interruptss (void) { | |
int value = digitalRead(ps2Keyboard_DataPin); | |
// This is the code to send a byte to the keyboard. Actually its 12 bits: | |
// a start bit, 8 data bits, 1 parity, 1 stop bit, 1 ack bit (from the kbd) | |
if (cmd_in_progress) { | |
cmd_count++; // cmd_count keeps track of the shifting | |
switch (cmd_count) { | |
case 1: // start bit | |
digitalWrite(ps2Keyboard_DataPin,LOW); | |
break; | |
case 2: case 3: case 4: case 5: case 6: case 7: case 8: case 9: | |
// data bits to shift | |
digitalWrite(ps2Keyboard_DataPin,cmd_value&1); | |
cmd_value = cmd_value>>1; | |
break; | |
case 10: // parity bit | |
digitalWrite(ps2Keyboard_DataPin,cmd_parity); | |
break; | |
case 11: // stop bit | |
// release the data pin, so stop bit actually relies on pull-up | |
// but this ensures the data pin is ready to be driven by the kbd for | |
// for the next bit. | |
digitalWrite(ps2Keyboard_DataPin, HIGH); | |
pinMode(ps2Keyboard_DataPin, INPUT); | |
break; | |
case 12: // ack bit - driven by the kbd, so we read its value | |
cmd_ack_value = digitalRead(ps2Keyboard_DataPin); | |
cmd_in_progress = false; // done shifting out | |
} | |
return; // don't fall through to the receive section of the ISR | |
} | |
// receive section of the ISR | |
// shift the bits in | |
// if(ps2Keyboard_BufferPos > 0 && ps2Keyboard_BufferPos < 11) { | |
if(ps2Keyboard_BufferPos < 11) { | |
ps2Keyboard_CurrentBuffer |= (value << (ps2Keyboard_BufferPos - 1)); | |
} | |
ps2Keyboard_BufferPos++; // keep track of shift-in position | |
if(ps2Keyboard_BufferPos == 11) { // a complete character received | |
// | |
switch (ps2Keyboard_CurrentBuffer) { | |
case 0xF0: { // key release char | |
ps2Keyboard_release = true; | |
ps2Keyboard_extend = false; | |
break; | |
} | |
case 0xFA: { // command acknowlegde byte | |
cmd_ack_byte_ok = true; | |
break; | |
} | |
case 0xE0: { // extended char set | |
ps2Keyboard_extend = true; | |
break; | |
} | |
case 0x12: // left shift | |
case 0x59: { // right shift | |
ps2Keyboard_shift = ps2Keyboard_release? false : true; | |
ps2Keyboard_release = false; | |
break; | |
} | |
case 0x11: { // alt key (right alt is extended 0x11) | |
ps2Keyboard_alt = ps2Keyboard_release? false : true; | |
ps2Keyboard_release = false; | |
break; | |
} | |
case 0x14: { // ctrl key (right ctrl is extended 0x14) | |
ps2Keyboard_ctrl = ps2Keyboard_release? false : true; | |
ps2Keyboard_release = false; | |
break; | |
} | |
case 0x58: { // caps lock key | |
if (!ps2Keyboard_release) { | |
ps2Keyboard_caps_lock = ps2Keyboard_caps_lock? false : true; | |
// allow caps lock code through to enable light on and off | |
//setfifo(ps2Keyboard_CurrentBuffer) ; | |
} | |
else { | |
ps2Keyboard_release = false; | |
} | |
break; | |
} | |
default: { // a real key | |
if (ps2Keyboard_release) { // although ignore if its just released | |
ps2Keyboard_release = false; | |
} | |
else { // real keys go into CharBuffer | |
//setfifo(ps2Keyboard_CurrentBuffer) ; | |
} | |
} | |
} | |
//setfifo(ps2Keyboard_CurrentBuffer) ; /// | |
ps2Keyboard_CurrentBuffer = 0; | |
ps2Keyboard_BufferPos = 0; | |
} | |
} | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
// PS2Keyboard | |
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |
PS2Keyboard::PS2Keyboard() { | |
// nothing to do here | |
} | |
void PS2Keyboard::reset() { | |
kbd_send_command(0xFF); // send the kbd reset code to the kbd: 3 lights | |
// should flash briefly on the kbd | |
v_initialize(); | |
} | |
void PS2Keyboard::begin(int dataPin) { | |
v_initialize(); | |
// Prepare the global variables | |
ps2Keyboard_DataPin = dataPin; | |
// initialize the pins | |
pinMode(PS2_INT_PIN, INPUT); | |
digitalWrite(PS2_INT_PIN, HIGH); | |
pinMode(dataPin, INPUT); | |
digitalWrite(dataPin, HIGH); | |
attachInterrupt(PS2_INT_NUM, ps2interrupt, FALLING); | |
#if 0 | |
// Global Enable INT1 interrupt | |
EIMSK |= ( 1 << INT1); | |
// Falling edge triggers interrupt | |
EICRA |= (0 << ISC10) | (1 << ISC11); | |
#endif | |
} | |
bool PS2Keyboard::available() { | |
if (tail == head) return 0; | |
return 1 ; | |
} | |
// This routine allows a calling program to see if other other keys are held | |
// down when a character is received: ie <ctrl>, <alt>, <shift> or <shift_lock> | |
// Note that this routine must be called after available() has returned true, | |
// but BEFORE read(). The read() routine clears the buffer and allows another | |
// character to be received so these bits can change anytime after the read(). | |
uint8_t PS2Keyboard::read_extra() { | |
return (ps2Keyboard_caps_lock<<3) | (ps2Keyboard_shift<<2) | (ps2Keyboard_alt<<1) | ps2Keyboard_ctrl; | |
} | |
uint8_t PS2Keyboard::rawread() { | |
return get_scan_code() ; | |
} | |
uint8_t PS2Keyboard::read() { | |
uint8_t result; | |
// result = getfifo() ; // read the raw data from the keyboard | |
// Use a switch for the code to character conversion. | |
// This is fast and actually only uses 4 bytes per simple line | |
switch (result) { | |
case 0x1C: result = 'a'; break; | |
case 0x32: result = 'b'; break; | |
case 0x21: result = 'c'; break; | |
case 0x23: result = 'd'; break; | |
case 0x24: result = 'e'; break; | |
case 0x2B: result = 'f'; break; | |
case 0x34: result = 'g'; break; | |
case 0x33: result = 'h'; break; | |
case 0x43: result = 'i'; break; | |
case 0x3B: result = 'j'; break; | |
case 0x42: result = 'k'; break; | |
case 0x4B: result = 'l'; break; | |
case 0x3A: result = 'm'; break; | |
case 0x31: result = 'n'; break; | |
case 0x44: result = 'o'; break; | |
case 0x4D: result = 'p'; break; | |
case 0x15: result = 'q'; break; | |
case 0x2D: result = 'r'; break; | |
case 0x1B: result = 's'; break; | |
case 0x2C: result = 't'; break; | |
case 0x3C: result = 'u'; break; | |
case 0x2A: result = 'v'; break; | |
case 0x1D: result = 'w'; break; | |
case 0x22: result = 'x'; break; | |
case 0x35: result = 'y'; break; | |
case 0x1A: result = 'z'; break; | |
// note that caps lock only used on a-z | |
case 0x41: result = ps2Keyboard_shift? '<' : ','; break; | |
case 0x49: result = ps2Keyboard_shift? '>' : '.'; break; | |
case 0x4A: result = ps2Keyboard_shift? '?' : '/'; break; | |
case 0x54: result = ps2Keyboard_shift? '{' : '['; break; | |
case 0x5B: result = ps2Keyboard_shift? '}' : ']'; break; | |
case 0x4E: result = ps2Keyboard_shift? '_' : '-'; break; | |
case 0x55: result = ps2Keyboard_shift? '+' : '='; break; | |
case 0x29: result = ' '; break; | |
case 0x45: result = ps2Keyboard_shift? ')' : '0'; break; | |
case 0x16: result = ps2Keyboard_shift? '!' : '1'; break; | |
case 0x1E: result = ps2Keyboard_shift? '@' : '2'; break; | |
case 0x26: result = ps2Keyboard_shift? '£' : '3'; break; | |
case 0x25: result = ps2Keyboard_shift? '$' : '4'; break; | |
case 0x2E: result = ps2Keyboard_shift? '%' : '5'; break; | |
case 0x36: result = ps2Keyboard_shift? '^' : '6'; break; | |
case 0x3D: result = ps2Keyboard_shift? '&' : '7'; break; | |
case 0x3E: result = ps2Keyboard_shift? '*' : '8'; break; | |
case 0x46: result = ps2Keyboard_shift? '(' : '9'; break; | |
case 0x0D: result = '\t'; break; | |
case 0x5A: result = '\n'; break; | |
case 0x66: result = PS2_KC_BKSP; break; | |
case 0x69: result = ps2Keyboard_extend? PS2_KC_END : '1'; break; | |
case 0x6B: result = ps2Keyboard_extend? PS2_KC_LEFT : '4'; break; | |
case 0x6C: result = ps2Keyboard_extend? PS2_KC_HOME : '7'; break; | |
case 0x70: result = ps2Keyboard_extend? PS2_KC_INS : '0'; break; | |
case 0x71: result = ps2Keyboard_extend? PS2_KC_DEL : '.'; break; | |
case 0x72: result = ps2Keyboard_extend? PS2_KC_DOWN : '2'; break; | |
case 0x73: result = '5'; break; | |
case 0x74: result = ps2Keyboard_extend? PS2_KC_RIGHT : '6'; break; | |
case 0x75: result = ps2Keyboard_extend? PS2_KC_UP : '8'; break; | |
case 0x76: result = PS2_KC_ESC; break; | |
case 0x79: result = '+'; break; | |
case 0x7A: result = ps2Keyboard_extend? PS2_KC_PGDN : '3'; break; | |
case 0x7B: result = '-'; break; | |
case 0x7C: result = '*'; break; | |
case 0x7D: result = ps2Keyboard_extend? PS2_KC_PGUP : '9'; break; | |
case 0x58: | |
// setting the keyboard lights is done here. Ideally it would be done | |
// in the interrupt routine itself and the key codes associated wth | |
// caps lock key presses would never be passed on as characters. | |
// However it would make the interrupt routine very messy with lots | |
// of extra state associated with the control of a caps_lock | |
// key code causing a cmd byte to transmit, causing an ack_byte to | |
// be received, then a data byte to transmit. Much easier done here. | |
// The downside, however, is that the light going on or off at the | |
// right time relies on the calling program to be checking for | |
// characters on a regular basis. If the calling program stops | |
// polling for characters at any point pressing the caps lock key | |
// will not change the state of the caps lock light while polling | |
// is not happening. | |
result = ps2Keyboard_caps_lock? PS2_KC_CLON : PS2_KC_CLOFF; | |
if (ps2Keyboard_caps_lock) kbd_set_lights(4); | |
else kbd_set_lights(0); | |
break; | |
// Reset the shift counter for unexpected values, to get back into sink | |
// This allows for hot plugging a keyboard in and out | |
default: delay(500); // but wait a bit in case part way through a shift | |
v_modifier_initialize(); | |
} // end switch(result) | |
// shift a-z chars here (less code than in the switch statement) | |
if (((result>='a') && (result<='z')) && | |
((ps2Keyboard_shift && !ps2Keyboard_caps_lock) || | |
(!ps2Keyboard_shift && ps2Keyboard_caps_lock))) { | |
result = result + ('A'-'a'); | |
} | |
return(result); | |
} |
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/* | |
PS2Keyboard.h - PS2Keyboard library | |
Copyright (c) 2007 Free Software Foundation. All right reserved. | |
Written by Christian Weichel <info@32leaves.net> | |
** Modified for use with Arduino 13 by L. Abraham Smith, <n3bah@microcompdesign.com> * | |
** Modified to include: shift, alt, caps_lock and caps_lock light by Bill Oldfield * | |
This library is free software; you can redistribute it and/or | |
modify it under the terms of the GNU Lesser General Public | |
License as published by the Free Software Foundation; either | |
version 2.1 of the License, or (at your option) any later version. | |
This library is distributed in the hope that it will be useful, | |
but WITHOUT ANY WARRANTY; without even the implied warranty of | |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
Lesser General Public License for more details. | |
You should have received a copy of the GNU Lesser General Public | |
License along with this library; if not, write to the Free Software | |
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
*/ | |
#ifndef PS2Keyboard_h | |
#define PS2Keyboard_h | |
#include <avr/io.h> | |
#include <avr/interrupt.h> | |
#include <avr/pgmspace.h> | |
/* | |
* PS2 keyboard "make" codes to check for certain keys. | |
*/ | |
// Give these codes that aren't used by anything else | |
// Making all the control key codes above 0x80 makes it simple to check for | |
// printable characters at the calling level. | |
#define PS2_KC_BKSP 0x80 | |
#define PS2_KC_UP 0x81 | |
#define PS2_KC_DOWN 0x82 | |
#define PS2_KC_LEFT 0x83 | |
#define PS2_KC_RIGHT 0x84 | |
#define PS2_KC_PGDN 0x85 | |
#define PS2_KC_PGUP 0x86 | |
#define PS2_KC_END 0x87 | |
#define PS2_KC_HOME 0x88 | |
#define PS2_KC_INS 0x89 | |
#define PS2_KC_DEL 0x8A | |
#define PS2_KC_ESC 0x8B | |
#define PS2_KC_CLON 0x8C // caps_lock on | |
#define PS2_KC_CLOFF 0x8D // caps_lock off | |
#include "binary.h" | |
typedef uint8_t boolean; | |
/* | |
* This PIN is hardcoded in the init routine later on. If you change this | |
* make sure you change the interrupt initialization as well. | |
PS2_INT_PIN 2 / attachInterrupt(0, ps2interrupt, FALLING); | |
PS2_INT_PIN 3 / attachInterrupt(1, ps2interrupt, FALLING); | |
*/ | |
#define PS2_INT_PIN 2 | |
#define PS2_INT_NUM 0 | |
/** | |
* Purpose: Provides an easy access to PS2 keyboards | |
* Author: Christian Weichel | |
*/ | |
class PS2Keyboard { | |
private: | |
int m_dataPin; | |
uint8_t m_charBuffer; | |
public: | |
/** | |
* This constructor does basically nothing. Please call the begin(int) | |
* method before using any other method of this class. | |
*/ | |
PS2Keyboard(); | |
/** | |
* Starts the keyboard "service" by registering the external interrupt. | |
* setting the pin modes correctly and driving those needed to high. | |
* The propably best place to call this method is in the setup routine. | |
*/ | |
void begin(int dataPin); | |
/** | |
* Returns true if there is a char to be read, false if not. | |
*/ | |
bool available(); | |
/** | |
* Sends a reset command to the keyboard and re-initialises all the control | |
* variables within the PS2Keybaord code. | |
*/ | |
void reset(); | |
/** | |
* Returns the char last read from the keyboard. If the user has pressed two | |
* keys between calls to this method, only the later one will be availble. Once | |
* the char has been read, the buffer will be cleared. | |
* If there is no char availble, 0 is returned. | |
*/ | |
uint8_t read(); | |
uint8_t rawread(); | |
/** | |
* Returns the status of the <ctrl> key, the <alt> key, the <shift> key and the | |
* caps_lock state. Note that shift and caps_lock are handled within the | |
* Ps2Keyboard code (and the return value from read() is already modified), but | |
* being able to read them here may be useful. | |
* This routine is optional BUT MUST ONLY be read after available() has returned | |
* true and BEFORE read() is called to retrieve the character. Reading it after | |
* the call to read() will return unpredictable values. | |
*/ | |
uint8_t read_extra(); | |
}; | |
#endif |
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// 20120703 Arduino IDE1.0.1 | |
// Arduino UNO R3 INT_NUM=0,PIN=2 / INT_NUM=1,PIN=3 | |
// Arduino Leonardo INT_NUM=0,PIN=3 / INT_NUM=1,PIN=2 (wrong) | |
#define INT_NUM 1 | |
#define INT_PIN 3 | |
int led = 13; | |
volatile int state = LOW; | |
void setup() | |
{ | |
pinMode(led, OUTPUT); | |
pinMode(INT_PIN, INPUT_PULLUP); | |
attachInterrupt(INT_NUM, blink, CHANGE); | |
} | |
void loop() | |
{ | |
digitalWrite(led, state); | |
} | |
void blink() | |
{ | |
state = !state; | |
} |
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