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@@ -1,216 +0,0 @@
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-// Bit-banged implementation without any use of interrupts.
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-// Data pin must have external 1K pull-up resistor.
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-// Operates data pin as open-collector output.
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-
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-#include "adb_blargg.h"
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-
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-#ifdef HAVE_CONFIG_H
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- #include "config.h"
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-#endif
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-
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-#include <avr/io.h>
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-#include <avr/interrupt.h>
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-#include <util/delay.h>
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-
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-// Copyright 2011 Jun WAKO <wakojun@gmail.com>
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-// Copyright 2013 Shay Green <gblargg@gmail.com>
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-// See bottom of file for license
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-
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-typedef uint8_t byte;
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-
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-// Make loop iteration take us total, including cyc overhead of loop logic
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-#define delay_loop_usec( us, cyc ) \
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- __builtin_avr_delay_cycles( (unsigned long) (F_CPU / 1e6 * (us) + 0.5) - (cyc) )
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-
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-#if !defined(ADB_PORT) || \
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- !defined(ADB_PIN) || \
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- !defined(ADB_DDR) || \
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- !defined(ADB_DATA_BIT)
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- #error
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-#endif
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-
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-enum { data_mask = 1<<ADB_DATA_BIT };
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-
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-enum { adb_cmd_read = 0x2C };
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-enum { adb_cmd_write = 0x28 };
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-
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-// gcc is very unreliable for inlining, so use macros
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-#define data_lo() (ADB_DDR |= data_mask)
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-#define data_hi() (ADB_DDR &= ~data_mask)
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-#define data_in() (ADB_PIN & data_mask)
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-
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-static void place_bit( byte bit )
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-{
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- // 100 us bit cell time
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- data_lo();
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- _delay_us( 35 );
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-
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- // Difference between a 0 and 1 bit is just this 30us portion in the middle
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- if ( bit )
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- data_hi();
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- _delay_us( 30 );
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-
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- data_hi();
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- _delay_us( 35 );
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-}
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-
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-static void place_bit0( void ) { place_bit( 0 ); }
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-static void place_bit1( void ) { place_bit( 1 ); }
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-
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-static void send_byte( byte data )
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-{
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- for ( byte n = 8; n; n-- )
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- {
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- place_bit( data & 0x80 );
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- data <<= 1;
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- }
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-}
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-
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-static void command( byte cmd )
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-{
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- data_lo();
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- _delay_us( 800 );
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- place_bit1();
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- send_byte( cmd );
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- place_bit0();
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-}
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-
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-void adb_host_init( void )
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-{
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- // Always keep port output 0, then just toggle DDR to be GND or leave it floating (high).
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- ADB_DDR &= ~data_mask;
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- ADB_PORT &= ~data_mask;
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-
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- #ifdef ADB_PSW_BIT
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- // Weak pull-up
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- ADB_PORT |= (1<<ADB_PSW_BIT);
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- ADB_DDR &= ~(1<<ADB_PSW_BIT);
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- #endif
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-}
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-
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-bool adb_host_psw( void )
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-{
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- #ifdef ADB_PSW_BIT
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- return (ADB_PIN & (1<<ADB_PSW_BIT)) != 0;
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- #else
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- return true;
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- #endif
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-}
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-
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-// Waits while data == val, or until us timeout expires. Returns remaining time,
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-// zero if timed out.
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-static byte while_data( byte us, byte data )
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-{
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- while ( data_in() == data )
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- {
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- delay_loop_usec( 1 /* us period */, 7 /* cycles loop overhead */ );
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- if ( !--us )
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- break;
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- }
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- return us;
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-}
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-
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-static byte while_lo( byte us ) { return while_data( us, 0 ); }
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-static byte while_hi( byte us ) { return while_data( us, data_mask ); }
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-
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-static uint16_t adb_host_talk( byte cmd )
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-{
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- command( cmd );
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- _delay_us( 5 );
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- if ( !while_hi( 260 - 5 ) ) // avg 160
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- return adb_host_nothing;
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-
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- // Receive start bit and 16 data bits.
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- // Doing them all in loop allows consistent error checking
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- uint16_t data = 0;
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- byte n = 17;
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- do
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- {
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- data <<= 1;
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- enum { timeout = 130 }; // maximum bit cell time
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-
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- byte lo = while_lo( timeout );
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- if ( !lo )
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- goto error; // timeout
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-
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- byte hi = while_hi( lo );
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- if ( !hi )
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- goto error; // timeout
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-
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- if ( timeout-lo < lo-hi )
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- data |= 1;
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- else if ( n == 17 )
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- goto error; // start bit is wrong
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- }
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- while ( --n );
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-
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- // duration must be split in two due to 255 limit
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- if ( !while_lo( 255 ) && !while_lo( 351 - 255 ) )
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- goto error;
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-
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- if ( while_hi( 91 ) )
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- goto error;
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-
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- return data;
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-
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-error:
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- return adb_host_error;
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-}
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-
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-uint16_t adb_host_kbd_recv( void )
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-{
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- return adb_host_talk( adb_cmd_read + 0 );
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-}
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-
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-uint16_t adb_host_kbd_modifiers( void )
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-{
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- return adb_host_talk( adb_cmd_read + 2 );
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-}
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-
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-void adb_host_listen( byte cmd, byte data_h, byte data_l )
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-{
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- command( cmd );
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- _delay_us( 200 );
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-
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- place_bit1();
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- send_byte( data_h );
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- send_byte( data_l );
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- place_bit0();
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-}
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-
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-void adb_host_kbd_led( byte led )
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-{
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- adb_host_listen( adb_cmd_write + 2, 0, led & 0x07 );
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-}
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-
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-/* This software is licensed with a Modified BSD License.
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-All of this is supposed to be Free Software, Open Source, DFSG-free,
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-GPL-compatible, and OK to use in both free and proprietary applications.
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-Additions and corrections to this file are welcome.
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-
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-Redistribution and use in source and binary forms, with or without
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-modification, are permitted provided that the following conditions are met:
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-
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-* Redistributions of source code must retain the above copyright
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- notice, this list of conditions and the following disclaimer.
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-
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-* Redistributions in binary form must reproduce the above copyright
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- notice, this list of conditions and the following disclaimer in
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- the documentation and/or other materials provided with the
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- distribution.
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-
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-* Neither the name of the copyright holders nor the names of
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- contributors may be used to endorse or promote products derived
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- from this software without specific prior written permission.
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-
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-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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-POSSIBILITY OF SUCH DAMAGE. */
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tmk