Files
arduino-library-lolshield/lib/Charliplexing.cpp
T

357 lines
11 KiB
C++

/*
Charliplexing.cpp - Using timer2 with 1ms resolution
Alex Wenger <a.wenger@gmx.de> http://arduinobuch.wordpress.com/
Matt Mets <mahto@cibomahto.com> http://cibomahto.com/
Timer init code from MsTimer2 - Javier Valencia <javiervalencia80@gmail.com>
Misc functions from Benjamin Sonnatg <benjamin@sonntag.fr>
History:
2009-12-30 - V0.0 wrote the first version at 26C3/Berlin
2010-01-01 - V0.1 adding misc utility functions
(Clear, Vertical, Horizontal) comment are Doxygen complaints now
2010-05-27 - V0.2 add double-buffer mode
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 "WProgram.h"
#include <inttypes.h>
#include <avr/interrupt.h>
#include "Charliplexing.h"
volatile unsigned int LedSign::tcnt2;
/* ----------------------------------------------------------------- */
/** Table for the LED multiplexing cycles, containing 12 cycles made out of two bytes
*/
uint8_t leds[2][24];
/// Determines whether the display is in single or double buffer mode
uint8_t displayMode;
/// Flag indicating that the display page should be flipped as soon as the
/// current frame is displayed
boolean videoFlipPage;
/// Pointer to the buffer that is currently being displayed
uint8_t* displayBuffer;
/// Pointer to the buffer that should currently be drawn to
uint8_t* workBuffer;
/// Number of timer counts to display each row for
uint8_t timeOn;
/// Number of timer counts between screen displays
uint8_t timeOff;
uint8_t statusPIN = 19;
boolean onPhase;
/* ----------------------------------------------------------------- */
/** Table for LED Position in leds[] ram table
*/
const uint16_t ledMap[252] = {
13, 5,13, 6,13, 7,13, 8,13, 9,13,10,13,11,13,12,13, 4, 4,13,13, 3, 3,13,13, 2, 2,13,
12, 5,12, 6,12, 7,12, 8,12, 9,12,10,12,11,12,13,12, 4, 4,12,12, 3, 3,12,12, 2, 2,12,
11, 5,11, 6,11, 7,11, 8,11, 9,11,10,11,12,11,13,11, 4, 4,11,11, 3, 3,11,11, 2, 2,11,
10, 5,10, 6,10, 7,10, 8,10, 9,10,11,10,12,10,13,10, 4, 4,10,10, 3, 3,10,10, 2, 2,10,
9, 5, 9, 6, 9, 7, 9, 8, 9,10, 9,11, 9,12, 9,13, 9, 4, 4, 9, 9, 3, 3, 9, 9, 2, 2, 9,
8, 5, 8, 6, 8, 7, 8, 9, 8,10, 8,11, 8,12, 8,13, 8, 4, 4, 8, 8, 3, 3, 8, 8, 2, 2, 8,
7, 5, 7, 6, 7, 8, 7, 9, 7,10, 7,11, 7,12, 7,13, 7, 4, 4, 7, 7, 3, 3, 7, 7, 2, 2, 7,
6, 5, 6, 7, 6, 8, 6, 9, 6,10, 6,11, 6,12, 6,13, 6, 4, 4, 6, 6, 3, 3, 6, 6, 2, 2, 6,
5, 6, 5, 7, 5, 8, 5, 9, 5,10, 5,11, 5,12, 5,13, 5, 4, 4, 5, 5, 3, 3, 5, 5, 2, 2, 5,
};
/* ----------------------------------------------------------------- */
/** Constructor : Initialize the interrupt code.
* should be called in setup();
*/
void LedSign::Init(uint8_t mode)
{
pinMode(statusPIN, OUTPUT);
digitalWrite(statusPIN, LOW);
float prescaler = 0.0;
#if defined (__AVR_ATmega168__) || defined (__AVR_ATmega48__) || defined (__AVR_ATmega88__) || defined (__AVR_ATmega328P__) || (__AVR_ATmega1280__)
TIMSK2 &= ~(1<<TOIE2);
TCCR2A &= ~((1<<WGM21) | (1<<WGM20));
TCCR2B &= ~(1<<WGM22);
ASSR &= ~(1<<AS2);
TIMSK2 &= ~(1<<OCIE2A);
if ((F_CPU >= 1000000UL) && (F_CPU <= 16000000UL)) { // prescaler set to 64
TCCR2B |= (1<<CS22);
TCCR2B &= ~((1<<CS21) | (1<<CS20));
prescaler = 64.0;
} else if (F_CPU < 1000000UL) { // prescaler set to 8
TCCR2B |= (1<<CS21);
TCCR2B &= ~((1<<CS22) | (1<<CS20));
prescaler = 8.0;
} else { // F_CPU > 16Mhz, prescaler set to 128
TCCR2B |= ((1<<CS22) | (1<<CS20));
TCCR2B &= ~(1<<CS21);
prescaler = 128.0;
}
#elif defined (__AVR_ATmega8__)
TIMSK &= ~(1<<TOIE2);
TCCR2 &= ~((1<<WGM21) | (1<<WGM20));
TIMSK &= ~(1<<OCIE2);
ASSR &= ~(1<<AS2);
if ((F_CPU >= 1000000UL) && (F_CPU <= 16000000UL)) { // prescaler set to 64
TCCR2 |= (1<<CS22);
TCCR2 &= ~((1<<CS21) | (1<<CS20));
prescaler = 64.0;
} else if (F_CPU < 1000000UL) { // prescaler set to 8
TCCR2 |= (1<<CS21);
TCCR2 &= ~((1<<CS22) | (1<<CS20));
prescaler = 8.0;
} else { // F_CPU > 16Mhz, prescaler set to 128
TCCR2 |= ((1<<CS22) && (1<<CS20));
TCCR2 &= ~(1<<CS21);
prescaler = 128.0;
}
#elif defined (__AVR_ATmega128__)
TIMSK &= ~(1<<TOIE2);
TCCR2 &= ~((1<<WGM21) | (1<<WGM20));
TIMSK &= ~(1<<OCIE2);
if ((F_CPU >= 1000000UL) && (F_CPU <= 16000000UL)) { // prescaler set to 64
TCCR2 |= ((1<<CS21) | (1<<CS20));
TCCR2 &= ~(1<<CS22);
prescaler = 64.0;
} else if (F_CPU < 1000000UL) { // prescaler set to 8
TCCR2 |= (1<<CS21);
TCCR2 &= ~((1<<CS22) | (1<<CS20));
prescaler = 8.0;
} else { // F_CPU > 16Mhz, prescaler set to 256
TCCR2 |= (1<<CS22);
TCCR2 &= ~((1<<CS21) | (1<<CS20));
prescaler = 256.0;
}
#endif
tcnt2 = 256 - (int)((float)F_CPU * 0.001 / prescaler);
LedSign::SetBrightness(127);
#if defined (__AVR_ATmega168__) || defined (__AVR_ATmega48__) || defined (__AVR_ATmega88__) || defined (__AVR_ATmega328P__) || (__AVR_ATmega1280__)
TCNT2 = tcnt2;
TIMSK2 |= (1<<TOIE2);
#elif defined (__AVR_ATmega128__)
TCNT2 = tcnt2;
TIMSK |= (1<<TOIE2);
#elif defined (__AVR_ATmega8__)
TCNT2 = tcnt2;
TIMSK |= (1<<TOIE2);
#endif
// Record whether we are in single or double buffer mode
displayMode = mode;
// Point the display buffer to the first physical buffer
displayBuffer = leds[0];
// If we are in single buffered mode, point the work buffer
// at the same physical buffer as the display buffer. Otherwise,
// point it at the second physical buffer.
if( displayMode == SINGLE_BUFFER ) {
workBuffer = displayBuffer;
}
else {
workBuffer = leds[1];
}
// Clear the buffer and display it
LedSign::Clear(0);
LedSign::Flip(false);
}
/* ----------------------------------------------------------------- */
/** Clear the screen completely
* @param blocking if true : wait for flip before returning, if false :
* return immediately.
*/
void LedSign::Flip(bool blocking)
{
if (displayMode == DOUBLE_BUFFER)
{
// Just set the flip flag, the buffer will flip between redraws
videoFlipPage = true;
// If we are blocking, sit here until the page flips.
while (blocking && videoFlipPage) {
delay(1);
}
}
}
/* ----------------------------------------------------------------- */
/** Clear the screen completely
* @param set if 1 : make all led ON, if not set or 0 : make all led OFF
*/
void LedSign::Clear(int set) {
for(int x=0;x<14;x++)
for(int y=0;y<9;y++)
Set(x,y,set);
}
/* ----------------------------------------------------------------- */
/** Clear an horizontal line completely
* @param y is the y coordinate of the line to clear/light [0-8]
* @param set if 1 : make all led ON, if not set or 0 : make all led OFF
*/
void LedSign::Horizontal(int y, int set) {
for(int x=0;x<14;x++)
Set(x,y,set);
}
/* ----------------------------------------------------------------- */
/** Clear a vertical line completely
* @param x is the x coordinate of the line to clear/light [0-13]
* @param set if 1 : make all led ON, if not set or 0 : make all led OFF
*/
void LedSign::Vertical(int x, int set) {
for(int y=0;y<9;y++)
Set(x,y,set);
}
/* ----------------------------------------------------------------- */
/** Set : switch on and off the leds. All the position
* calculations are done here, so we don't need to do in the
* interrupt code
*/
void LedSign::Set(uint8_t x, uint8_t y, uint8_t c)
{
uint8_t pin_low = ledMap[x*2+y*28+1];
uint8_t pin_high = ledMap[x*2+y*28+0];
// pin_low is directly the address in the led array (minus 2 because the
// first two bytes are used for RS232 communication), but
// as it is a two byte array we need to check pin_high also.
// If pin_high is bigger than 8 address has to be increased by one
if (c == 1) {
workBuffer[(pin_low-2)*2 + (pin_high / 8)] |= _BV(pin_high & 0x07); // ON
}
else {
workBuffer[(pin_low-2)*2 + (pin_high / 8)] &= ~_BV(pin_high & 0x07); // OFF
}
}
/* Set the overall brightness of the screen
* @param brightness LED brightness, from 0 (off) to 127 (full on)
*/
void LedSign::SetBrightness(uint8_t brightness)
{
// An exponential fit seems to approximate a (percieved) linear scale
float brightnessPercent = ((float)brightness / 127)*((float)brightness / 127);
// Compute on and off times
uint8_t interval = 255 - tcnt2;
int newTimeOn = 255 -brightnessPercent*interval;
int newTimeOff = 255 - (1 - brightnessPercent)*interval;
// Then update the registers
timeOn = newTimeOn;
timeOff = newTimeOff;
}
/* ----------------------------------------------------------------- */
/** The Interrupt code goes here !
*/
ISR(TIMER2_OVF_vect) {
digitalWrite(statusPIN, HIGH);
if (!onPhase) {
onPhase = true;
}
else {
if (timeOff > 0) {
onPhase = false;
}
}
if ( onPhase ) {
#if defined (__AVR_ATmega168__) || defined (__AVR_ATmega48__) || defined (__AVR_ATmega88__) || defined (__AVR_ATmega328P__) || (__AVR_ATmega1280__)
TCNT2 = timeOn;
#elif defined (__AVR_ATmega128__)
TCNT2 = timeOn;
#elif defined (__AVR_ATmega8__)
TCNT2 = timeOn;
#endif
// 12 Cycles of Matrix
static uint8_t i = 0;
if (i < 6) {
DDRD = _BV(i+2) | displayBuffer[i*2];
PORTD = displayBuffer[i*2];
DDRB = displayBuffer[i*2+1];
PORTB = displayBuffer[i*2+1];
} else {
DDRD = displayBuffer[i*2];
PORTD = displayBuffer[i*2];
DDRB = _BV(i-6) | displayBuffer[i*2+1];
PORTB = displayBuffer[i*2+1];
}
i++;
if (i > 12) {
i = 0;
// If the page should be flipped, do it here.
if (videoFlipPage && displayMode == DOUBLE_BUFFER)
{
// TODO: is this an atomic operation?
videoFlipPage = false;
uint8_t* temp = displayBuffer;
displayBuffer = workBuffer;
workBuffer = temp;
}
}
}
else {
#if defined (__AVR_ATmega168__) || defined (__AVR_ATmega48__) || defined (__AVR_ATmega88__) || defined (__AVR_ATmega328P__) || (__AVR_ATmega1280__)
TCNT2 = timeOff;
#elif defined (__AVR_ATmega128__)
TCNT2 = timeOff;
#elif defined (__AVR_ATmega8__)
TCNT2 = timeOff;
#endif
// Turn everything off
DDRD = 0x0;
DDRB = 0x0;
}
digitalWrite(statusPIN, LOW);
}