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Diffstat (limited to 'tmk_core/protocol/xt_interrupt.c')
| -rw-r--r-- | tmk_core/protocol/xt_interrupt.c | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/tmk_core/protocol/xt_interrupt.c b/tmk_core/protocol/xt_interrupt.c deleted file mode 100644 index ba9d71848f..0000000000 --- a/tmk_core/protocol/xt_interrupt.c +++ /dev/null @@ -1,166 +0,0 @@ -/* -Copyright 2018 Jun WAKO <wakojun@gmail.com> -Copyright 2016 Ethan Apodaca <papodaca@gmail.com> - -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. -*/ - -#include <stdbool.h> -#include <avr/interrupt.h> -#include "xt.h" -#include "wait.h" -#include "debug.h" - -static inline uint8_t pbuf_dequeue(void); -static inline void pbuf_enqueue(uint8_t data); -static inline bool pbuf_has_data(void); -static inline void pbuf_clear(void); - -void xt_host_init(void) { - XT_INT_INIT(); - XT_INT_OFF(); - - /* hard reset */ -#ifdef XT_RESET - XT_RESET(); -#endif - - /* soft reset: pull clock line down for 20ms */ - XT_DATA_LO(); - XT_CLOCK_LO(); - wait_ms(20); - - /* input mode with pullup */ - XT_CLOCK_IN(); - XT_DATA_IN(); - - XT_INT_ON(); -} - -/* get data received by interrupt */ -uint8_t xt_host_recv(void) { - if (pbuf_has_data()) { - return pbuf_dequeue(); - } else { - return 0; - } -} - -ISR(XT_INT_VECT) { - /* - * XT signal format consits of 10 or 9 clocks and sends start bits and 8-bit data, - * which should be read on falling edge of clock. - * - * start(0), start(1), bit0, bit1, bit2, bit3, bit4, bit5, bit6, bit7 - * - * Original IBM XT keyboard sends start(0) bit while some of clones don't. - * Start(0) bit is read as low on data line while start(1) as high. - * - * https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-XT-Keyboard-Protocol - */ - static enum { START, BIT0, BIT1, BIT2, BIT3, BIT4, BIT5, BIT6, BIT7 } state = START; - static uint8_t data = 0; - - uint8_t dbit = XT_DATA_READ(); - - // This is needed if using PCINT which can be called on both falling and rising edge - // if (XT_CLOCK_READ()) return; - - switch (state) { - case START: - // ignore start(0) bit - if (!dbit) return; - break; - case BIT0 ... BIT7: - data >>= 1; - if (dbit) data |= 0x80; - break; - } - if (state++ == BIT7) { - pbuf_enqueue(data); - state = START; - data = 0; - } - return; -} - -/*-------------------------------------------------------------------- - * Ring buffer to store scan codes from keyboard - *------------------------------------------------------------------*/ -#define PBUF_SIZE 32 -static uint8_t pbuf[PBUF_SIZE]; -static uint8_t pbuf_head = 0; -static uint8_t pbuf_tail = 0; - -static inline void pbuf_enqueue(uint8_t data) { - uint8_t sreg = SREG; - cli(); - uint8_t next = (pbuf_head + 1) % PBUF_SIZE; - if (next != pbuf_tail) { - pbuf[pbuf_head] = data; - pbuf_head = next; - } else { - dprintf("pbuf: full\n"); - } - SREG = sreg; -} - -static inline uint8_t pbuf_dequeue(void) { - uint8_t val = 0; - - uint8_t sreg = SREG; - cli(); - if (pbuf_head != pbuf_tail) { - val = pbuf[pbuf_tail]; - pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE; - } - SREG = sreg; - - return val; -} - -static inline bool pbuf_has_data(void) { - uint8_t sreg = SREG; - cli(); - bool has_data = (pbuf_head != pbuf_tail); - SREG = sreg; - return has_data; -} - -static inline void pbuf_clear(void) { - uint8_t sreg = SREG; - cli(); - pbuf_head = pbuf_tail = 0; - SREG = sreg; -} |