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-rw-r--r--tmk_core/protocol/serial_soft.c240
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diff --git a/tmk_core/protocol/serial_soft.c b/tmk_core/protocol/serial_soft.c
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+++ b/tmk_core/protocol/serial_soft.c
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+/*
+Copyright 2012 Jun WAKO <wakojun@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/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include "serial.h"
+
+/*
+ * Stupid Inefficient Busy-wait Software Serial
+ * which is still useful for negative logic signal like Sun protocol
+ * if it is not supported by hardware UART.
+ *
+ * TODO: delay is not accurate enough. Instruction cycle should be counted and inline assemby is needed.
+ */
+
+#define WAIT_US (1000000L/SERIAL_SOFT_BAUD)
+
+#ifdef SERIAL_SOFT_LOGIC_NEGATIVE
+ #define SERIAL_SOFT_RXD_IN() !(SERIAL_SOFT_RXD_READ())
+ #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_LO()
+ #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_HI()
+#else
+ #define SERIAL_SOFT_RXD_IN() !!(SERIAL_SOFT_RXD_READ())
+ #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_HI()
+ #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_LO()
+#endif
+
+#ifdef SERIAL_SOFT_PARITY_EVEN
+ #define SERIAL_SOFT_PARITY_VAL 0
+#elif defined(SERIAL_SOFT_PARITY_ODD)
+ #define SERIAL_SOFT_PARITY_VAL 1
+#endif
+
+/* debug for signal timing, see debug pin with oscilloscope */
+#define SERIAL_SOFT_DEBUG
+#ifdef SERIAL_SOFT_DEBUG
+ #define SERIAL_SOFT_DEBUG_INIT() (DDRD |= 1<<7)
+ #define SERIAL_SOFT_DEBUG_TGL() (PORTD ^= 1<<7)
+#else
+ #define SERIAL_SOFT_DEBUG_INIT()
+ #define SERIAL_SOFT_DEBUG_TGL()
+#endif
+
+
+void serial_init(void)
+{
+ SERIAL_SOFT_DEBUG_INIT();
+
+ SERIAL_SOFT_RXD_INIT();
+ SERIAL_SOFT_TXD_INIT();
+}
+
+/* RX ring buffer */
+#define RBUF_SIZE 8
+static uint8_t rbuf[RBUF_SIZE];
+static uint8_t rbuf_head = 0;
+static uint8_t rbuf_tail = 0;
+
+
+uint8_t serial_recv(void)
+{
+ uint8_t data = 0;
+ if (rbuf_head == rbuf_tail) {
+ return 0;
+ }
+
+ data = rbuf[rbuf_tail];
+ rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
+ return data;
+}
+
+int16_t serial_recv2(void)
+{
+ uint8_t data = 0;
+ if (rbuf_head == rbuf_tail) {
+ return -1;
+ }
+
+ data = rbuf[rbuf_tail];
+ rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
+ return data;
+}
+
+void serial_send(uint8_t data)
+{
+ /* signal state: IDLE: ON, START: OFF, STOP: ON, DATA0: OFF, DATA1: ON */
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+ #ifdef SERIAL_SOFT_DATA_7BIT
+ uint8_t mask = 0x40;
+ #else
+ uint8_t mask = 0x80;
+ #endif
+#else
+ uint8_t mask = 0x01;
+#endif
+
+ uint8_t parity = 0;
+
+ /* start bit */
+ SERIAL_SOFT_TXD_OFF();
+ _delay_us(WAIT_US);
+
+#ifdef SERIAL_SOFT_DATA_7BIT
+ while (mask&0x7F) {
+#else
+ while (mask&0xFF) {
+#endif
+ if (data&mask) {
+ SERIAL_SOFT_TXD_ON();
+ parity ^= 1;
+ } else {
+ SERIAL_SOFT_TXD_OFF();
+ }
+ _delay_us(WAIT_US);
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+ mask >>= 1;
+#else
+ mask <<= 1;
+#endif
+ }
+
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+ /* to center of parity bit */
+ if (parity != SERIAL_SOFT_PARITY_VAL) {
+ SERIAL_SOFT_TXD_ON();
+ } else {
+ SERIAL_SOFT_TXD_OFF();
+ }
+ _delay_us(WAIT_US);
+#endif
+
+ /* stop bit */
+ SERIAL_SOFT_TXD_ON();
+ _delay_us(WAIT_US);
+}
+
+/* detect edge of start bit */
+ISR(SERIAL_SOFT_RXD_VECT)
+{
+ SERIAL_SOFT_DEBUG_TGL();
+ SERIAL_SOFT_RXD_INT_ENTER()
+
+ uint8_t data = 0;
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+ #ifdef SERIAL_SOFT_DATA_7BIT
+ uint8_t mask = 0x40;
+ #else
+ uint8_t mask = 0x80;
+ #endif
+#else
+ uint8_t mask = 0x01;
+#endif
+
+ uint8_t parity = 0;
+
+ /* to center of start bit */
+ _delay_us(WAIT_US/2);
+ SERIAL_SOFT_DEBUG_TGL();
+ do {
+ /* to center of next bit */
+ _delay_us(WAIT_US);
+
+ SERIAL_SOFT_DEBUG_TGL();
+ if (SERIAL_SOFT_RXD_IN()) {
+ data |= mask;
+ parity ^= 1;
+ }
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+ mask >>= 1;
+#else
+ mask <<= 1;
+#endif
+#ifdef SERIAL_SOFT_DATA_7BIT
+ } while (mask&0x7F);
+#else
+ } while (mask&0xFF);
+#endif
+
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+ /* to center of parity bit */
+ _delay_us(WAIT_US);
+ if (SERIAL_SOFT_RXD_IN()) { parity ^= 1; }
+ SERIAL_SOFT_DEBUG_TGL();
+#endif
+
+ /* to center of stop bit */
+ _delay_us(WAIT_US);
+
+ uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+ if ((parity == SERIAL_SOFT_PARITY_VAL) && next != rbuf_tail) {
+#else
+ if (next != rbuf_tail) {
+#endif
+ rbuf[rbuf_head] = data;
+ rbuf_head = next;
+ }
+
+ SERIAL_SOFT_RXD_INT_EXIT();
+ SERIAL_SOFT_DEBUG_TGL();
+}