forked from mfulz_github/qmk_firmware
		
	* Update ADB impelmentation in tmk_core to recent version. Pcked from tmk_keyboard repository revision: 48d696443857512d45f9a7329e0dd0a76345860f * Restore convenient ADB functions used in QMK port. * Do cformat.
		
			
				
	
	
		
			536 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			536 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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Copyright 2011-19 Jun WAKO <wakojun@gmail.com>
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Copyright 2013 Shay Green <gblargg@gmail.com>
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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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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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* 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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* 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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* 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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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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*/
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#include <stdbool.h>
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#include <util/delay.h>
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#include <avr/io.h>
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#include <avr/interrupt.h>
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#include "adb.h"
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#include "print.h"
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// GCC doesn't inline functions normally
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#define data_lo() (ADB_DDR |= (1 << ADB_DATA_BIT))
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#define data_hi() (ADB_DDR &= ~(1 << ADB_DATA_BIT))
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#define data_in() (ADB_PIN & (1 << ADB_DATA_BIT))
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#ifdef ADB_PSW_BIT
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static inline void psw_lo(void);
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static inline void psw_hi(void);
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static inline bool psw_in(void);
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#endif
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static inline void     attention(void);
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static inline void     place_bit0(void);
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static inline void     place_bit1(void);
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static inline void     send_byte(uint8_t data);
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static inline uint16_t wait_data_lo(uint16_t us);
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static inline uint16_t wait_data_hi(uint16_t us);
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void adb_host_init(void) {
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    ADB_PORT &= ~(1 << ADB_DATA_BIT);
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    data_hi();
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#ifdef ADB_PSW_BIT
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    psw_hi();
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#endif
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}
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#ifdef ADB_PSW_BIT
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bool adb_host_psw(void) { return psw_in(); }
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#endif
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/*
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 * Don't call this in a row without the delay, otherwise it makes some of poor controllers
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 * overloaded and misses strokes. Recommended interval is 12ms.
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 *
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 * Thanks a lot, blargg!
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 * <http://geekhack.org/index.php?topic=14290.msg1068919#msg1068919>
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 * <http://geekhack.org/index.php?topic=14290.msg1070139#msg1070139>
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 */
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uint16_t adb_host_kbd_recv(void) { return adb_host_talk(ADB_ADDR_KEYBOARD, ADB_REG_0); }
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#ifdef ADB_MOUSE_ENABLE
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__attribute__((weak)) void adb_mouse_init(void) { return; }
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__attribute__((weak)) void adb_mouse_task(void) { return; }
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uint16_t adb_host_mouse_recv(void) { return adb_host_talk(ADB_ADDR_MOUSE, ADB_REG_0); }
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#endif
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// This sends Talk command to read data from register and returns length of the data.
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uint8_t adb_host_talk_buf(uint8_t addr, uint8_t reg, uint8_t *buf, uint8_t len) {
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    for (int8_t i = 0; i < len; i++) buf[i] = 0;
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    cli();
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    attention();
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    send_byte((addr << 4) | ADB_CMD_TALK | reg);
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    place_bit0();  // Stopbit(0)
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    // TODO: Service Request(Srq):
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    // Device holds low part of comannd stopbit for 140-260us
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    //
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    // Command:
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    // ......._     ______________________    ___ ............_     -------
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    //         |   |                      |  |   |             |   |
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    // Command |   |                      |  |   | Data bytes  |   |
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    // ........|___|  |     140-260       |__|   |_............|___|
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    //         |stop0 | Tlt Stop-to-Start |start1|             |stop0 |
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    //
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    // Command without data:
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    // ......._     __________________________
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    //         |   |
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    // Command |   |
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    // ........|___|  |     140-260       |
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    //         |stop0 | Tlt Stop-to-Start |
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    //
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    // Service Request:
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    // ......._                     ______    ___ ............_     -------
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    //         |     140-260       |      |  |   |             |   |
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    // Command |  Service Request  |      |  |   | Data bytes  |   |
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    // ........|___________________|      |__|   |_............|___|
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    //         |stop0 |                   |start1|             |stop0 |
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    // ......._                     __________
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    //         |     140-260       |
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    // Command |  Service Request  |
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    // ........|___________________|
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    //         |stop0 |
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    // This can be happened?
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    // ......._     ______________________    ___ ............_                   -----
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    //         |   |                      |  |   |             |    140-260      |
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    // Command |   |                      |  |   | Data bytes  | Service Request |
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    // ........|___|  |     140-260       |__|   |_............|_________________|
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    //         |stop0 | Tlt Stop-to-Start |start1|             |stop0 |
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    //
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    // "Service requests are issued by the devices during a very specific time at the
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    // end of the reception of the command packet.
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    // If a device in need of service issues a service request, it must do so within
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    // the 65 µs of the Stop Bit’s low time and maintain the line low for a total of 300 µs."
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    //
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    // "A device sends a Service Request signal by holding the bus low during the low
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    // portion of the stop bit of any command or data transaction. The device must lengthen
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    // the stop by a minimum of 140 J.lS beyond its normal duration, as shown in Figure 8-15."
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    // http://ww1.microchip.com/downloads/en/AppNotes/00591b.pdf
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    if (!wait_data_hi(500)) {  // Service Request(310us Adjustable Keyboard): just ignored
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        xprintf("R");
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        sei();
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        return 0;
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    }
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    if (!wait_data_lo(500)) {  // Tlt/Stop to Start(140-260us)
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        sei();
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        return 0;  // No data from device(not error);
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    }
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    // start bit(1)
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    if (!wait_data_hi(40)) {
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        xprintf("S");
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        sei();
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        return 0;
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    }
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    if (!wait_data_lo(100)) {
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        xprintf("s");
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        sei();
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        return 0;
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    }
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    uint8_t n = 0;  // bit count
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    do {
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        //
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        // |<- bit_cell_max(130) ->|
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        // |        |<-   lo     ->|
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        // |        |       |<-hi->|
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        //           _______
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        // |        |       |
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        // | 130-lo | lo-hi |
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        // |________|       |
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        //
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        uint8_t lo = (uint8_t)wait_data_hi(130);
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        if (!lo) goto error;  // no more bit or after stop bit
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        uint8_t hi = (uint8_t)wait_data_lo(lo);
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        if (!hi) goto error;  // stop bit extedned by Srq?
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        if (n / 8 >= len) continue;  // can't store in buf
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        buf[n / 8] <<= 1;
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        if ((130 - lo) < (lo - hi)) {
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            buf[n / 8] |= 1;
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        }
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    } while (++n);
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error:
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    sei();
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    return n / 8;
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}
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uint16_t adb_host_talk(uint8_t addr, uint8_t reg) {
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    uint8_t len;
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    uint8_t buf[8];
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    len = adb_host_talk_buf(addr, reg, buf, 8);
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    if (len != 2) return 0;
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    return (buf[0] << 8 | buf[1]);
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}
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void adb_host_listen_buf(uint8_t addr, uint8_t reg, uint8_t *buf, uint8_t len) {
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    cli();
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    attention();
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    send_byte((addr << 4) | ADB_CMD_LISTEN | reg);
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    place_bit0();  // Stopbit(0)
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    // TODO: Service Request
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    _delay_us(200);  // Tlt/Stop to Start
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    place_bit1();    // Startbit(1)
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    for (int8_t i = 0; i < len; i++) {
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        send_byte(buf[i]);
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        // xprintf("%02X ", buf[i]);
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    }
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    place_bit0();  // Stopbit(0);
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    sei();
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}
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void adb_host_listen(uint8_t addr, uint8_t reg, uint8_t data_h, uint8_t data_l) {
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    uint8_t buf[2] = {data_h, data_l};
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    adb_host_listen_buf(addr, reg, buf, 2);
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}
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void adb_host_flush(uint8_t addr) {
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    cli();
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    attention();
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    send_byte((addr << 4) | ADB_CMD_FLUSH);
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    place_bit0();    // Stopbit(0)
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    _delay_us(200);  // Tlt/Stop to Start
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    sei();
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}
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// send state of LEDs
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void adb_host_kbd_led(uint8_t led) {
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    // Listen Register2
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    //  upper byte: not used
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    //  lower byte: bit2=ScrollLock, bit1=CapsLock, bit0=NumLock
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    adb_host_listen(ADB_ADDR_KEYBOARD, ADB_REG_2, 0, led & 0x07);
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}
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#ifdef ADB_PSW_BIT
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static inline void psw_lo() {
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    ADB_DDR |= (1 << ADB_PSW_BIT);
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    ADB_PORT &= ~(1 << ADB_PSW_BIT);
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}
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static inline void psw_hi() {
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    ADB_PORT |= (1 << ADB_PSW_BIT);
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    ADB_DDR &= ~(1 << ADB_PSW_BIT);
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}
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static inline bool psw_in() {
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    ADB_PORT |= (1 << ADB_PSW_BIT);
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    ADB_DDR &= ~(1 << ADB_PSW_BIT);
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    return ADB_PIN & (1 << ADB_PSW_BIT);
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}
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#endif
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static inline void attention(void) {
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    data_lo();
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    _delay_us(800 - 35);  // bit1 holds lo for 35 more
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    place_bit1();
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}
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static inline void place_bit0(void) {
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    data_lo();
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    _delay_us(65);
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    data_hi();
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    _delay_us(35);
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}
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static inline void place_bit1(void) {
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    data_lo();
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    _delay_us(35);
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    data_hi();
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    _delay_us(65);
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}
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static inline void send_byte(uint8_t data) {
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    for (int i = 0; i < 8; i++) {
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        if (data & (0x80 >> i))
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            place_bit1();
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        else
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            place_bit0();
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    }
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}
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// These are carefully coded to take 6 cycles of overhead.
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// inline asm approach became too convoluted
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static inline uint16_t wait_data_lo(uint16_t us) {
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    do {
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        if (!data_in()) break;
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        _delay_us(1 - (6 * 1000000.0 / F_CPU));
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    } while (--us);
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    return us;
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}
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static inline uint16_t wait_data_hi(uint16_t us) {
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    do {
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        if (data_in()) break;
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        _delay_us(1 - (6 * 1000000.0 / F_CPU));
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    } while (--us);
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    return us;
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}
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/*
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ADB Protocol
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============
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Resources
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---------
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ADB - The Untold Story: Space Aliens Ate My Mouse
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    http://developer.apple.com/legacy/mac/library/#technotes/hw/hw_01.html
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ADB Manager
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    http://developer.apple.com/legacy/mac/library/documentation/mac/pdf/Devices/ADB_Manager.pdf
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    Service request(5-17)
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Apple IIgs Hardware Reference Second Edition [Chapter6 p121]
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    ftp://ftp.apple.asimov.net/pub/apple_II/documentation/Apple%20IIgs%20Hardware%20Reference.pdf
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ADB Keycode
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    http://72.0.193.250/Documentation/macppc/adbkeycodes/
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    http://m0115.web.fc2.com/m0115.jpg
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    [Inside Macintosh volume V, pages 191-192]
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    http://www.opensource.apple.com/source/IOHIDFamily/IOHIDFamily-421.18.3/IOHIDFamily/Cosmo_USB2ADB.c
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ADB Signaling
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    http://kbdbabel.sourceforge.net/doc/kbd_signaling_pcxt_ps2_adb.pdf
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ADB Overview & History
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    http://en.wikipedia.org/wiki/Apple_Desktop_Bus
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Microchip Application Note: ADB device(with code for PIC16C)
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    http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011062
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AVR ATtiny2131 ADB to PS/2 converter(Japanese)
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    http://hp.vector.co.jp/authors/VA000177/html/KeyBoardA5DEA5CBA5A2II.html
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Pinouts
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-------
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    ADB female socket from the front:
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    __________
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    |        | <--- top
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    | 4o  o3 |
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    |2o    o1|
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    |   ==   |
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    |________| <--- bottom
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      |    |   <--- 4pins
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    ADB female socket from bottom:
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    ========== <--- front
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    |        |
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    |        |
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    |2o    o1|
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    |4o    o3|
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    ---------- <--- back
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    1: Data
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    2: Power SW(low when press Power key)
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    3: Vcc(5V)
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    4: GND
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 | 
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Commands
 | 
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--------
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    ADB command is 1byte and consists of 4bit-address, 2bit-command
 | 
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    type and 2bit-register. The commands are always sent by Host.
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 | 
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    Command format:
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    7 6 5 4 3 2 1 0
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    | | | |------------ address
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            | |-------- command type
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                | |---- register
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    bits                commands
 | 
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    ------------------------------------------------------
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    - - - - 0 0 0 0     Send Reset(reset all devices)
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    A A A A 0 0 0 1     Flush(reset a device)
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    - - - - 0 0 1 0     Reserved
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    - - - - 0 0 1 1     Reserved
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    - - - - 0 1 - -     Reserved
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    A A A A 1 0 R R     Listen(write to a device)
 | 
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    A A A A 1 1 R R     Talk(read from a device)
 | 
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 | 
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    The command to read keycodes from keyboard is 0x2C which
 | 
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    consist of keyboard address 2 and Talk against register 0.
 | 
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 | 
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    Address:
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    2:  keyboard
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    3:  mice
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 | 
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    Registers:
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    0: application(keyboard uses this to store its data.)
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    1: application
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    2: application(keyboard uses this for LEDs and state of modifiers)
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    3: status and command
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 | 
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 | 
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Communication
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-------------
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    This is a minimum information for keyboard communication.
 | 
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    See "Resources" for detail.
 | 
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 | 
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    Signaling:
 | 
						||
 | 
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    ~~~~____________~~||||||||||||__~~~~~_~~|||||||||||||||__~~~~
 | 
						||
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        |800us     |  |7 Command 0|  |   |  |15-64  Data  0|Stopbit(0)
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        +Attention |              |  |   +Startbit(1)
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                   +Startbit(1)   |  +Tlt(140-260us)
 | 
						||
                                  +stopbit(0)
 | 
						||
 | 
						||
    Bit cells:
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 | 
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    bit0: ______~~~
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          65    :35us
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 | 
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    bit1: ___~~~~~~
 | 
						||
          35 :65us
 | 
						||
 | 
						||
    bit0 low time: 60-70% of bit cell(42-91us)
 | 
						||
    bit1 low time: 30-40% of bit cell(21-52us)
 | 
						||
    bit cell time: 70-130us
 | 
						||
    [from Apple IIgs Hardware Reference Second Edition]
 | 
						||
 | 
						||
    Criterion for bit0/1:
 | 
						||
    After 55us if line is low/high then bit is 0/1.
 | 
						||
 | 
						||
    Attention & start bit:
 | 
						||
    Host asserts low in 560-1040us then places start bit(1).
 | 
						||
 | 
						||
    Tlt(Stop to Start):
 | 
						||
    Bus stays high in 140-260us then device places start bit(1).
 | 
						||
 | 
						||
    Global reset:
 | 
						||
    Host asserts low in 2.8-5.2ms. All devices are forced to reset.
 | 
						||
 | 
						||
    Service request from device(Srq):
 | 
						||
    Device can request to send at commad(Global only?) stop bit.
 | 
						||
    Requesting device keeps low for 140-260us at stop bit of command.
 | 
						||
 | 
						||
 | 
						||
Keyboard Data(Register0)
 | 
						||
    This 16bit data can contains two keycodes and two released flags.
 | 
						||
    First keycode is palced in upper byte. When one keyocode is sent,
 | 
						||
    lower byte is 0xFF.
 | 
						||
    Release flag is 1 when key is released.
 | 
						||
 | 
						||
    1514 . . . . . 8 7 6 . . . . . 0
 | 
						||
     | | | | | | | | | +-+-+-+-+-+-+-   Keycode2
 | 
						||
     | | | | | | | | +---------------   Released2(1 when the key is released)
 | 
						||
     | +-+-+-+-+-+-+-----------------   Keycode1
 | 
						||
     +-------------------------------   Released1(1 when the key is released)
 | 
						||
 | 
						||
    Keycodes:
 | 
						||
    Scancode consists of 7bit keycode and 1bit release flag.
 | 
						||
    Device can send two keycodes at once. If just one keycode is sent
 | 
						||
    keycode1 contains it and keyocode2 is 0xFF.
 | 
						||
 | 
						||
    Power switch:
 | 
						||
    You can read the state from PSW line(active low) however
 | 
						||
    the switch has a special scancode 0x7F7F, so you can
 | 
						||
    also read from Data line. It uses 0xFFFF for release scancode.
 | 
						||
 | 
						||
Keyboard LEDs & state of keys(Register2)
 | 
						||
    This register hold current state of three LEDs and nine keys.
 | 
						||
    The state of LEDs can be changed by sending Listen command.
 | 
						||
 | 
						||
    1514 . . . . . . 7 6 5 . 3 2 1 0
 | 
						||
     | | | | | | | | | | | | | | | +-   LED1(NumLock)
 | 
						||
     | | | | | | | | | | | | | | +---   LED2(CapsLock)
 | 
						||
     | | | | | | | | | | | | | +-----   LED3(ScrollLock)
 | 
						||
     | | | | | | | | | | +-+-+-------   Reserved
 | 
						||
     | | | | | | | | | +-------------   ScrollLock
 | 
						||
     | | | | | | | | +---------------   NumLock
 | 
						||
     | | | | | | | +-----------------   Apple/Command
 | 
						||
     | | | | | | +-------------------   Option
 | 
						||
     | | | | | +---------------------   Shift
 | 
						||
     | | | | +-----------------------   Control
 | 
						||
     | | | +-------------------------   Reset/Power
 | 
						||
     | | +---------------------------   CapsLock
 | 
						||
     | +-----------------------------   Delete
 | 
						||
     +-------------------------------   Reserved
 | 
						||
 | 
						||
Address, Handler ID and bits(Register3)
 | 
						||
    1514131211 . . 8 7 . . . . . . 0
 | 
						||
     | | | | | | | | | | | | | | | |
 | 
						||
     | | | | | | | | +-+-+-+-+-+-+-+-   Handler ID
 | 
						||
     | | | | +-+-+-+-----------------   Address
 | 
						||
     | | | +-------------------------   0
 | 
						||
     | | +---------------------------   Service request enable(1 = enabled)
 | 
						||
     | +-----------------------------   Exceptional event(alwyas 1 if not used)
 | 
						||
     +-------------------------------   0
 | 
						||
 | 
						||
ADB Bit Cells
 | 
						||
    bit cell time: 70-130us
 | 
						||
    low part of bit0: 60-70% of bit cell
 | 
						||
    low part of bit1: 30-40% of bit cell
 | 
						||
 | 
						||
       bit cell time         70us        130us
 | 
						||
       --------------------------------------------
 | 
						||
       low  part of bit0     42-49       78-91
 | 
						||
       high part of bit0     21-28       39-52
 | 
						||
       low  part of bit1     21-28       39-52
 | 
						||
       high part of bit1     42-49       78-91
 | 
						||
 | 
						||
 | 
						||
    bit0:
 | 
						||
       70us bit cell:
 | 
						||
         ____________~~~~~~
 | 
						||
         42-49        21-28
 | 
						||
 | 
						||
       130us bit cell:
 | 
						||
         ____________~~~~~~
 | 
						||
         78-91        39-52
 | 
						||
 | 
						||
    bit1:
 | 
						||
       70us bit cell:
 | 
						||
         ______~~~~~~~~~~~~
 | 
						||
         21-28        42-49
 | 
						||
 | 
						||
       130us bit cell:
 | 
						||
         ______~~~~~~~~~~~~
 | 
						||
         39-52        78-91
 | 
						||
 | 
						||
    [from Apple IIgs Hardware Reference Second Edition]
 | 
						||
 | 
						||
Keyboard Handle ID
 | 
						||
    Apple Standard Keyboard M0116:      0x01
 | 
						||
    Apple Extended Keyboard M0115:      0x02
 | 
						||
    Apple Extended Keyboard II M3501:   0x02
 | 
						||
    Apple Adjustable Keybaord:          0x10
 | 
						||
 | 
						||
    http://lxr.free-electrons.com/source/drivers/macintosh/adbhid.c?v=4.4#L802
 | 
						||
 | 
						||
END_OF_ADB
 | 
						||
*/
 |