Michel2/New-LiquidCrystal-softwareheritage
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added fio_digitalWrite_SWITCH

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This commit is contained in:
flo
2012-01-26 01:44:31 +01:00
parent 7b2a7290c6
commit 0f49bd2c29
3 changed files with 42 additions and 12 deletions
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FastIO.cpp
+18 -6
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@@ -6,9 +6,9 @@
#include "FastIO.h"
#include <util/delay.h>
fio_register fio_pinToOutputRegister(uint8_t pin){
fio_register fio_pinToOutputRegister(uint8_t pin, uint8_t initial_state){
pinMode(pin, OUTPUT);
digitalWrite(pin, LOW); // also turns off pwm timer
if(initial_state != SKIP) digitalWrite(pin, initial_state); // also turns off pwm timer
#ifdef FIO_FALLBACK
// just wasting memory if not using fast io...
return 0;
@@ -66,7 +66,8 @@ void fio_shiftOut(fio_register dataRegister, fio_bit dataBit, fio_register clock
for(int8_t i = 7; i>-1; --i){
fio_digitalWrite(dataRegister, dataBit, !!(value & (1 << i)));
fio_digitalWrite_HIGH(clockRegister, clockBit);
fio_digitalWrite_LOW(clockRegister, clockBit);
// Switching is a little bit faster
fio_digitalWrite_SWITCH(clockRegister,clockBit);
}
// # enable interrupts
@@ -74,18 +75,23 @@ void fio_shiftOut(fio_register dataRegister, fio_bit dataBit, fio_register clock
}
void fio_shiftOut(fio_register dataRegister, uint8_t dataBit, fio_register clockRegister, uint8_t clockBit){
// shift out 0x0 (0b00000000) fast
fio_digitalWrite_LOW(dataRegister, dataBit);
for(uint8_t i = 0; i<8; ++i){
fio_digitalWrite_HIGH(clockRegister, clockBit);
fio_digitalWrite_LOW(clockRegister, clockBit);
fio_digitalWrite_HIGH(clockRegister, clockBit);
fio_digitalWrite_SWITCH(clockRegister,clockBit);
}
}
void fio_shiftOut1_init(fio_register shift1Register, fio_bit shift1Bit){
// Make sure that capacitors are charged
// 300us is an educated guess...
fio_digitalWrite(shift1Register,shift1Bit,HIGH);
delayMicroseconds(300);
}
void fio_shiftOut1_init(uint8_t pin){
fio_shiftOut1_init(fio_pinToOutputRegister(pin,HIGH),fio_pinToBit(pin));
}
void fio_shiftOut1(fio_register shift1Register, fio_bit shift1Bit, uint8_t value){
// disable interrupts since timing is going to be critical
@@ -93,14 +99,16 @@ void fio_shiftOut1(fio_register shift1Register, fio_bit shift1Bit, uint8_t value
oldSREG = SREG;
cli();
//unsigned int msLOW, msHIGH;
// note: profiling showed that shift out takes 18us longer than the sum of needed delays
// iterate but ignore last byte (must be LOW)
for(int8_t i = 7; i>0; --i){
fio_digitalWrite_LOW(shift1Register,shift1Bit);
if(LOW==!!(value & (1 << i))){
// LOW = 0 Bit
fio_digitalWrite_LOW(shift1Register,shift1Bit);
// hold pin LOW for 15us
delayMicroseconds(14);
fio_digitalWrite_HIGH(shift1Register,shift1Bit);
@@ -108,6 +116,7 @@ void fio_shiftOut1(fio_register shift1Register, fio_bit shift1Bit, uint8_t value
delayMicroseconds(29);
}else{
// HIGH = 1 Bit
fio_digitalWrite_LOW(shift1Register,shift1Bit);
//hold pin LOW for 1us - did that already
fio_digitalWrite_HIGH(shift1Register,shift1Bit);
//hold pin HIGH for 15us
@@ -124,4 +133,7 @@ void fio_shiftOut1(fio_register shift1Register, fio_bit shift1Bit, uint8_t value
SREG = oldSREG;
}
void fio_shiftOut1(uint8_t pin, uint8_t value){
fio_shiftOut1(fio_pinToOutputRegister(pin, SKIP),fio_pinToBit(pin),value);
}