/* Copyright 2010,2011,2012,2013 Jun WAKO */ #include #include #include "debug.h" #include "ring_buffer.h" #include "ibm4704.h" #define WAIT(stat, us, err) do { \ if (!wait_##stat(us)) { \ ibm4704_error = err; \ goto ERROR; \ } \ } while (0) uint8_t ibm4704_error = 0; void ibm4704_init(void) { inhibit(); // keep keyboard from sending IBM4704_INT_INIT(); IBM4704_INT_ON(); idle(); // allow keyboard sending } /* Host to Keyboard ---------------- Data bits are LSB first and Parity is odd. Clock has around 60us high and 30us low part. ____ __ __ __ __ __ __ __ __ __ ________ Clock \______/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ ^ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ___ Data ____|__/ X____X____X____X____X____X____X____X____X____X \___ | Start 0 1 2 3 4 5 6 7 P Stop Request by host Start bit: can be long as 300-350us. Request: Host pulls Clock line down to request to send a command. Timing: After Request keyboard pull up Data and down Clock line to low for start bit. After request host release Clock line once Data line becomes hi. Host writes a bit while Clock is hi and Keyboard reads while low. Stop bit: Host releases or pulls up Data line to hi after 9th clock and waits for keyboard pull down the line to lo. */ uint8_t ibm4704_send(uint8_t data) { bool parity = true; // odd parity ibm4704_error = 0; IBM4704_INT_OFF(); /* Request to send */ idle(); clock_lo(); /* wait for Start bit(Clock:lo/Data:hi) */ WAIT(data_hi, 300, 0x30); /* Data bit */ for (uint8_t i = 0; i < 8; i++) { WAIT(clock_hi, 100, 0x40+i); if (data&(1< 0x30) { xprintf("S:%02X ", ibm4704_error); } IBM4704_INT_ON(); return -1; } /* wait forever to receive data */ uint8_t ibm4704_recv_response(void) { while (!rbuf_has_data()) { _delay_ms(1); } return rbuf_dequeue(); } uint8_t ibm4704_recv(void) { if (rbuf_has_data()) { return rbuf_dequeue(); } else { return -1; } } /* Keyboard to Host ---------------- Data bits are LSB first and Parity is odd. Clock has around 60us high and 30us low part. ____ __ __ __ __ __ __ __ __ __ _______ Clock \_____/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ \_/ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ Data ____/ X____X____X____X____X____X____X____X____X____X________ Start 0 1 2 3 4 5 6 7 P Stop Start bit: can be long as 300-350us. Inhibit: Pull Data line down to inhibit keyboard to send. Timing: Host reads bit while Clock is hi.(rising edge) Stop bit: Keyboard pulls down Data line to lo after 9th clock. */ ISR(IBM4704_INT_VECT) { static enum { BIT0, BIT1, BIT2, BIT3, BIT4, BIT5, BIT6, BIT7, PARITY, STOP } state = BIT0; // LSB first static uint8_t data = 0; // Odd parity static uint8_t parity = false; ibm4704_error = 0; switch (state) { case BIT0: case BIT1: case BIT2: case BIT3: case BIT4: case BIT5: case BIT6: case BIT7: data >>= 1; if (data_in()) { data |= 0x80; parity = !parity; } break; case PARITY: if (data_in()) { parity = !parity; } if (!parity) goto ERROR; break; case STOP: // Data:Low WAIT(data_lo, 100, state); rbuf_enqueue(data); ibm4704_error = IBM4704_ERR_NONE; goto DONE; break; default: goto ERROR; } state++; goto RETURN; ERROR: ibm4704_error = state; while (ibm4704_send(0xFE)) _delay_ms(1); // resend xprintf("R:%02X%02X\n", state, data); DONE: state = BIT0; data = 0; parity = false; RETURN: return; } > 47 48 49 50 51 52 53 54 55 56 57 58 59 60 
/*
             LUFA Library
     Copyright (C) Dean Camera, 2010.
              
  dean [at] fourwalledcubicle [dot] com
      www.fourwalledcubicle.com
*/

/*
  Copyright 2010  David Prentice (david.prentice [at] farming [dot] uk)
  Copyright 2010  Peter Danneger
  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)

  Permission to use, copy, modify, distribute, and sell this 
  software and its documentation for any purpose is hereby granted
  without fee, provided that the above copyright notice appear in 
  all copies and that both that the copyright notice and this
  permission notice and warranty disclaimer appear in supporting 
  documentation, and that the name of the author not be used in 
  advertising or publicity pertaining to distribution of the 
  software without specific, written prior permission.

  The author disclaim all warranties with regard to this
  software, including all implied warranties of merchantability
  and fitness.  In no event shall the author be liable for any
  special, indirect or consequential damages or any damages
  whatsoever resulting from loss of use, data or profits, whether
  in an action of contract, negligence or other tortious action,
  arising out of or in connection with the use or performance of
  this software.
*/

#ifndef _SOFT_UART_
#define _SOFT_UART_

	/* Includes: */
		#include <avr/io.h>
		#include <avr/interrupt.h>
		#include "SoftUART.h"

	/* Macros: */
		#define BAUD       9600
		#define BIT_TIME   (uint16_t)((F_CPU + (BAUD / 2)) / BAUD)

		#define SRX        PD0
		#define SRXPIN     PIND
		#define SRXPORT    PORTD

		#define STX        PD1
		#define STXPORT    PORTD
		#define STXDDR     DDRD

	/* Function Prototypes: */
		uint8_t SoftUART_IsReady(void);
		uint8_t SoftUART_TxByte(uint8_t c);
		uint8_t SoftUART_IsReceived(void);
		uint8_t SoftUART_RxByte(void);
		void    SoftUART_Init(void);

#endif
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