diff options
Diffstat (limited to 'converter/adb_usb/adb_blargg.c')
| -rw-r--r-- | converter/adb_usb/adb_blargg.c | 216 |
1 files changed, 0 insertions, 216 deletions
diff --git a/converter/adb_usb/adb_blargg.c b/converter/adb_usb/adb_blargg.c deleted file mode 100644 index 963758c533..0000000000 --- a/converter/adb_usb/adb_blargg.c +++ /dev/null @@ -1,216 +0,0 @@ -// Bit-banged implementation without any use of interrupts. -// Data pin must have external 1K pull-up resistor. -// Operates data pin as open-collector output. - -#include "adb_blargg.h" - -#ifdef HAVE_CONFIG_H - #include "config.h" -#endif - -#include <avr/io.h> -#include <avr/interrupt.h> -#include <util/delay.h> - -// Copyright 2011 Jun WAKO <wakojun@gmail.com> -// Copyright 2013 Shay Green <gblargg@gmail.com> -// See bottom of file for license - -typedef uint8_t byte; - -// Make loop iteration take us total, including cyc overhead of loop logic -#define delay_loop_usec( us, cyc ) \ - __builtin_avr_delay_cycles( (unsigned long) (F_CPU / 1e6 * (us) + 0.5) - (cyc) ) - -#if !defined(ADB_PORT) || \ - !defined(ADB_PIN) || \ - !defined(ADB_DDR) || \ - !defined(ADB_DATA_BIT) - #error -#endif - -enum { data_mask = 1<<ADB_DATA_BIT }; - -enum { adb_cmd_read = 0x2C }; -enum { adb_cmd_write = 0x28 }; - -// gcc is very unreliable for inlining, so use macros -#define data_lo() (ADB_DDR |= data_mask) -#define data_hi() (ADB_DDR &= ~data_mask) -#define data_in() (ADB_PIN & data_mask) - -static void place_bit( byte bit ) -{ - // 100 us bit cell time - data_lo(); - _delay_us( 35 ); - - // Difference between a 0 and 1 bit is just this 30us portion in the middle - if ( bit ) - data_hi(); - _delay_us( 30 ); - - data_hi(); - _delay_us( 35 ); -} - -static void place_bit0( void ) { place_bit( 0 ); } -static void place_bit1( void ) { place_bit( 1 ); } - -static void send_byte( byte data ) -{ - for ( byte n = 8; n; n-- ) - { - place_bit( data & 0x80 ); - data <<= 1; - } -} - -static void command( byte cmd ) -{ - data_lo(); - _delay_us( 800 ); - place_bit1(); - send_byte( cmd ); - place_bit0(); -} - -void adb_host_init( void ) -{ - // Always keep port output 0, then just toggle DDR to be GND or leave it floating (high). - ADB_DDR &= ~data_mask; - ADB_PORT &= ~data_mask; - - #ifdef ADB_PSW_BIT - // Weak pull-up - ADB_PORT |= (1<<ADB_PSW_BIT); - ADB_DDR &= ~(1<<ADB_PSW_BIT); - #endif -} - -bool adb_host_psw( void ) -{ - #ifdef ADB_PSW_BIT - return (ADB_PIN & (1<<ADB_PSW_BIT)) != 0; - #else - return true; - #endif -} - -// Waits while data == val, or until us timeout expires. Returns remaining time, -// zero if timed out. -static byte while_data( byte us, byte data ) -{ - while ( data_in() == data ) - { - delay_loop_usec( 1 /* us period */, 7 /* cycles loop overhead */ ); - if ( !--us ) - break; - } - return us; -} - -static byte while_lo( byte us ) { return while_data( us, 0 ); } -static byte while_hi( byte us ) { return while_data( us, data_mask ); } - -static uint16_t adb_host_talk( byte cmd ) -{ - command( cmd ); - _delay_us( 5 ); - if ( !while_hi( 260 - 5 ) ) // avg 160 - return adb_host_nothing; - - // Receive start bit and 16 data bits. - // Doing them all in loop allows consistent error checking - uint16_t data = 0; - byte n = 17; - do - { - data <<= 1; - enum { timeout = 130 }; // maximum bit cell time - - byte lo = while_lo( timeout ); - if ( !lo ) - goto error; // timeout - - byte hi = while_hi( lo ); - if ( !hi ) - goto error; // timeout - - if ( timeout-lo < lo-hi ) - data |= 1; - else if ( n == 17 ) - goto error; // start bit is wrong - } - while ( --n ); - - // duration must be split in two due to 255 limit - if ( !while_lo( 255 ) && !while_lo( 351 - 255 ) ) - goto error; - - if ( while_hi( 91 ) ) - goto error; - - return data; - -error: - return adb_host_error; -} - -uint16_t adb_host_kbd_recv( void ) -{ - return adb_host_talk( adb_cmd_read + 0 ); -} - -uint16_t adb_host_kbd_modifiers( void ) -{ - return adb_host_talk( adb_cmd_read + 2 ); -} - -void adb_host_listen( byte cmd, byte data_h, byte data_l ) -{ - command( cmd ); - _delay_us( 200 ); - - place_bit1(); - send_byte( data_h ); - send_byte( data_l ); - place_bit0(); -} - -void adb_host_kbd_led( byte led ) -{ - adb_host_listen( adb_cmd_write + 2, 0, led & 0x07 ); -} - -/* This software is licensed with a Modified BSD License. -All of this is supposed to be Free Software, Open Source, DFSG-free, -GPL-compatible, and OK to use in both free and proprietary applications. -Additions and corrections to this file are welcome. - -Redistribution and use in source and binary forms, with or without -modification, are permitted provided that the following conditions are met: - -* Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - -* Redistributions in binary form must reproduce the above copyright - notice, this list of conditions and the following disclaimer in - the documentation and/or other materials provided with the - distribution. - -* Neither the name of the copyright holders nor the names of - contributors may be used to endorse or promote products derived - from this software without specific prior written permission. - -THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" -AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE -LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR -CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF -SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS -INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN -CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) -ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE -POSSIBILITY OF SUCH DAMAGE. */ |