diff options
Diffstat (limited to 'Projects/SerialToLCD/Lib/HD44780.c')
| -rw-r--r-- | Projects/SerialToLCD/Lib/HD44780.c | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/Projects/SerialToLCD/Lib/HD44780.c b/Projects/SerialToLCD/Lib/HD44780.c index cd825f8ef..a91e79310 100644 --- a/Projects/SerialToLCD/Lib/HD44780.c +++ b/Projects/SerialToLCD/Lib/HD44780.c @@ -1,13 +1,13 @@ /* LUFA Library - Copyright (C) Dean Camera, 2013. + Copyright (C) Dean Camera, 2014. dean [at] fourwalledcubicle [dot] com www.lufa-lib.org */ /* - Copyright 2013 Dean Camera (dean [at] fourwalledcubicle [dot] com) + Copyright 2014 Dean Camera (dean [at] fourwalledcubicle [dot] com) Copyright 2012 Simon Foster (simon.foster [at] inbox [dot] com) Permission to use, copy, modify, distribute, and sell this @@ -33,21 +33,21 @@ static void HD44780_WriteNibble(const uint8_t nib) { - /* Read PORTD and clear the ENABLE and PD0..3 bits + /* Read PORTD and clear the ENABLE and PD0..3 bits then OR in the data */ - + PORTD = (PORTD & ~(ENABLE | LO4_MASK)) | (nib & LO4_MASK); - - /* Enforce address setup time (tAS) 60ns - 60 @ 16MHz = <1 + + /* Enforce address setup time (tAS) 60ns + 60 @ 16MHz = <1 Let's us a few NOPs for good measure */ asm volatile("nop\n\t" "nop\n\t" :: ); - + /* Take enable high and enforce Enable High time (tEH=450ns) 450ns @ 16MHz = 7.2 => 7 NOPs */ - + PORTD |= ENABLE; asm volatile("nop\n\t" @@ -63,7 +63,7 @@ static void HD44780_WriteNibble(const uint8_t nib) /* Take enable low and enforce Enable Low time (tEL=500ns) 500ns @ 16MHz = 8.0 => 7 NOPs */ PORTD &= ~ENABLE; - + asm volatile("nop\n\t" "nop\n\t" "nop\n\t" @@ -90,11 +90,11 @@ static void HD44780_PowerUp4Bit(void) /* Wait for more than 4.1 ms */ _delay_ms(5); HD44780_WriteNibble(0x03); // FN_SET 8-bit - + /* Wait for more than 100 µs */ _delay_us(100); HD44780_WriteNibble(0x03); // FN_SET 8-bit - + /* From now on we must allow 40us for each command */ _delay_us(50); HD44780_WriteNibble(0x02); // FN_SET 4-bit |