rockbox/firmware/drivers/qt1106.c
Frank Gevaerts 816eea85de use bitwise operators to manipulate bits
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@18521 a1c6a512-1295-4272-9138-f99709370657
2008-09-15 18:48:11 +00:00

108 lines
2.4 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: $
*
* Copyright (C) 2008 by Frank Gevaerts
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "qt1106.h"
#include "cpu.h"
#include "system.h"
#define SPIDELAY(_x) void(_x);
#define SETMOSI() (PDAT1 |= (1 << 6))
#define CLRMOSI() (PDAT1 &= ~(1 << 6))
#define MISO ((PDAT0 >> 3) & 1)
#define RDY (PDAT1 & (1 << 5))
#define SETCLK() (PDAT0 |= (1 << 1))
#define CLRCLK() (PDAT0 &= ~(1 << 1))
#define SETSS() (PDAT0 |= (1 << 0))
#define CLRSS() (PDAT0 &= ~(1 << 0))
#define CHANGE (PDAT0 & (1 << 4))
void init_qt1106(void)
{
int oldval;
oldval = PCON0;
//Set P0.0 and P0.1 to output, set P0.3 and P0.4 to input
PCON0 = ((oldval & ~(3 << 0 | 3 << 2 | 3 << 6 | 3 << 8)) | (1 << 0 | 1 << 2));
oldval = PCON1;
//Set P1.5 to input, set P1.6 to output
PCON1 = ((oldval & ~(0xf << 20 | 0xf << 24)) | (1 << 24));
SETSS();
SETCLK();
}
static inline void delay(int duration)
{
volatile int i;
for(i=0;i<duration;i++);
}
void qt1106_wait(void)
{
while(!(PDAT0 & (1 << 4))) {}
}
unsigned int qt1106_io(unsigned int output)
{
unsigned int input = 0;
int i;
while(!RDY) {}
delay(10); // < 470 us
CLRSS();
delay(13); // > 22 us
for (i = 0; i < 24; i++) {
CLRCLK();
if (output & (1 << 23))
SETMOSI();
else
CLRMOSI();
output <<= 1;
delay(20); // >> 6.7 us
SETCLK();
input |= MISO;
input <<= 1;
delay(20); // >> 6.7 us
}
SETSS();
return (input);
}