Michel/arduino-library-lolshield
1
0
Fork 0
forked from Michel2/LoLshield
Code Pull Requests Activity

Add brightness control, to vary the intensity of the entire display.

Browse Source
This commit is contained in:
matt.mets
2010-07-21 02:07:26 +00:00
parent 8a3adf743c
commit e07ce62ddf
2 changed files with 99 additions and 43 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/Charliplexing.cpp
+98 -43
View File
@@ -53,6 +53,15 @@ 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
@@ -76,6 +85,9 @@ const uint16_t ledMap[252] = {
*/
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__)
@@ -138,6 +150,8 @@ void LedSign::Init(uint8_t mode)
#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;
@@ -246,56 +260,97 @@ void LedSign::Set(uint8_t x, uint8_t y, uint8_t c)
}
}
/* 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) {
#if defined (__AVR_ATmega168__) || defined (__AVR_ATmega48__) || defined (__AVR_ATmega88__) || defined (__AVR_ATmega328P__) || (__AVR_ATmega1280__)
TCNT2 = LedSign::tcnt2;
#elif defined (__AVR_ATmega128__)
TCNT2 = LedSign::tcnt2;
#elif defined (__AVR_ATmega8__)
TCNT2 = LedSign::tcnt2;
#endif
digitalWrite(statusPIN, HIGH);
// 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];
}
/*
PORTB = 0xff;
PORTD = i;
DDRB = 0xff;
DDRD = 0xff;
*/
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;
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);
}
lib/Charliplexing.h
+1
View File
@@ -18,6 +18,7 @@ namespace LedSign
{
extern void Init(uint8_t mode = SINGLE_BUFFER);
extern void Set(uint8_t x, uint8_t y, uint8_t c);
extern void SetBrightness(uint8_t brightness);
extern volatile unsigned int tcnt2;
extern void Flip(bool blocking = false);
extern void Clear(int set=0);