ibmpc: C++ class for two-interface support

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tmk 2021-07-04 22:02:08 +09:00
parent 0e3b7084b7
commit f4f47aaee7
2 changed files with 641 additions and 0 deletions

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/*
Copyright 2010,2011,2012,2013,2019 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.
*/
/*
* IBM PC keyboard protocol
*/
#include <stdbool.h>
#include <avr/interrupt.h>
#include <util/atomic.h>
#include "debug.h"
#include "timer.h"
#include "wait.h"
#include "ibmpc.hpp"
#define WAIT(stat, us, err) do { \
if (!wait_##stat(us)) { \
error = err; \
goto ERROR; \
} \
} while (0)
IBMPC IBMPC::interface0 = IBMPC(IBMPC_CLOCK_BIT, IBMPC_DATA_BIT);
#if defined(IBMPC_CLOCK_BIT1) && defined(IBMPC_DATA_BIT1)
IBMPC IBMPC::interface1 = IBMPC(IBMPC_CLOCK_BIT1, IBMPC_DATA_BIT1);
#endif
void IBMPC::host_init(void)
{
// initialize reset pin to HiZ
IBMPC_RST_HIZ();
inhibit();
int_init();
int_off();
ringbuf_init(&rb, rbuf, RINGBUF_SIZE);
host_isr_clear();
}
void IBMPC::host_enable(void)
{
int_on();
idle();
}
void IBMPC::host_disable(void)
{
int_off();
inhibit();
}
int16_t IBMPC::host_send(uint8_t data)
{
bool parity = true;
error = IBMPC_ERR_NONE;
uint8_t retry = 0;
dprintf("w%02X ", data);
// Not receiving data
if (isr_state != 0x8000) dprintf("isr:%04X ", isr_state);
while (isr_state != 0x8000) ;
// Not clock Lo
if (!clock_in()) dprintf("c:%u ", wait_clock_hi(1000));
// Not data Lo
if (!data_in()) dprintf("d:%u ", wait_data_hi(1000));
int_off();
RETRY:
/* terminate a transmission if we have */
inhibit();
wait_us(200); // [5]p.54
/* 'Request to Send' and Start bit */
data_lo();
wait_us(200);
clock_hi(); // [5]p.54 [clock low]>100us [5]p.50
WAIT(clock_lo, 10000, 1); // [5]p.53, -10ms [5]p.50
/* Data bit[2-9] */
for (uint8_t i = 0; i < 8; i++) {
wait_us(15);
if (data&(1<<i)) {
parity = !parity;
data_hi();
} else {
data_lo();
}
WAIT(clock_hi, 50, 2);
WAIT(clock_lo, 50, 3);
}
/* Parity bit */
wait_us(15);
if (parity) { data_hi(); } else { data_lo(); }
WAIT(clock_hi, 50, 4);
WAIT(clock_lo, 50, 5);
/* Stop bit */
wait_us(15);
data_hi();
/* Ack */
WAIT(data_lo, 300, 6);
WAIT(data_hi, 300, 7);
WAIT(clock_hi, 300, 8);
// clear buffer to get response correctly
host_isr_clear();
idle();
int_on();
return host_recv_response();
ERROR:
// Retry for Z-150 AT start bit error
if (error == 1 && retry++ < 10) {
error = IBMPC_ERR_NONE;
dprintf("R ");
goto RETRY;
}
error |= IBMPC_ERR_SEND;
inhibit();
wait_ms(2);
idle();
int_on();
return -1;
}
/*
* Receive data from keyboard
*/
int16_t IBMPC::host_recv(void)
{
int16_t ret = -1;
// Enable ISR if buffer was full
if (ringbuf_is_full(&rb)) {
host_isr_clear();
int_on();
idle();
}
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
ret = ringbuf_get(&rb);
}
if (ret != -1) dprintf("r%02X ", ret&0xFF);
return ret;
}
int16_t IBMPC::host_recv_response(void)
{
// Command may take 25ms/20ms at most([5]p.46, [3]p.21)
uint8_t retry = 25;
int16_t data = -1;
while (retry-- && (data = host_recv()) == -1) {
wait_ms(1);
}
return data;
}
void IBMPC::host_isr_clear(void)
{
isr_debug = 0;
protocol = 0;
error = 0;
isr_state = 0x8000;
ringbuf_reset(&rb);
}
inline void IBMPC::isr(void)
{
uint8_t dbit;
dbit = IBMPC_DATA_PIN&(1<<data_bit);
// Timeout check
uint8_t t;
// use only the least byte of millisecond timer
asm("lds %0, %1" : "=r" (t) : "p" (&timer_count));
//t = (uint8_t)timer_count; // compiler uses four registers instead of one
if (isr_state == 0x8000) {
timer_start = t;
} else {
// This gives 2.0ms at least before timeout
if ((uint8_t)(t - timer_start) >= 3) {
isr_debug = isr_state;
error = IBMPC_ERR_TIMEOUT;
goto ERROR;
// timeout error recovery - start receiving new data
// it seems to work somehow but may not under unstable situation
//timer_start = t;
//isr_state = 0x8000;
}
}
isr_state = isr_state>>1;
if (dbit) isr_state |= 0x8000;
// isr_state: state of receiving data from keyboard
//
// This should be initialized with 0x8000 before receiving data and
// the MSB '*1' works as marker to discrimitate between protocols.
// It stores sampled bit at MSB after right shift on each clock falling edge.
//
// XT protocol has two variants of signaling; XT_IBM and XT_Clone.
// XT_IBM uses two start bits 0 and 1 while XT_Clone uses just start bit 1.
// https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-XT-Keyboard-Protocol
//
// 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
// -----------------------------------------------------
// *1 0 0 0 0 0 0 0 | 0 0 0 0 0 0 0 0 Initial state(0x8000)
//
// x x x x x x x x | 0 0 0 0 0 0 0 0 midway(0-7 bits received)
// x x x x x x x x | *1 0 0 0 0 0 0 0 midway(8 bits received)
// b6 b5 b4 b3 b2 b1 b0 1 | 0 *1 0 0 0 0 0 0 XT_IBM-midway ^1
// b7 b6 b5 b4 b3 b2 b1 b0 | 0 *1 0 0 0 0 0 0 AT-midway ^1
// b7 b6 b5 b4 b3 b2 b1 b0 | 1 *1 0 0 0 0 0 0 XT_Clone-done ^3
// b6 b5 b4 b3 b2 b1 b0 1 | 1 *1 0 0 0 0 0 0 XT_IBM-error ^3
// pr b7 b6 b5 b4 b3 b2 b1 | 0 0 *1 0 0 0 0 0 AT-midway[b0=0]
// b7 b6 b5 b4 b3 b2 b1 b0 | 1 0 *1 0 0 0 0 0 XT_IBM-done ^2
// pr b7 b6 b5 b4 b3 b2 b1 | 1 0 *1 0 0 0 0 0 AT-midway[b0=1] ^2
// b7 b6 b5 b4 b3 b2 b1 b0 | 1 1 *1 0 0 0 0 0 XT_IBM-error-done
// x x x x x x x x | x 1 1 0 0 0 0 0 illegal
// st pr b7 b6 b5 b4 b3 b2 | b1 b0 0 *1 0 0 0 0 AT-done
// x x x x x x x x | x x 1 *1 0 0 0 0 illegal
// all other states than above illegal
//
// ^1: AT and XT_IBM takes same state.
// ^2: AT and XT_IBM takes same state in case that AT b0 is 1,
// we have to check AT stop bit to discriminate between the two protocol.
switch (isr_state & 0xFF) {
case 0b00000000:
case 0b10000000:
case 0b01000000: // ^1
case 0b00100000:
// midway
goto NEXT;
break;
case 0b11000000: // ^3
{
uint8_t us = 100;
// wait for rising and falling edge of b7 of XT_IBM
while (!(IBMPC_CLOCK_PIN&(1<<clock_bit)) && us) { wait_us(1); us--; }
while ( IBMPC_CLOCK_PIN&(1<<clock_bit) && us) { wait_us(1); us--; }
if (us) {
// XT_IBM-error: read start(0) as 1
goto NEXT;
} else {
// XT_Clone-done
isr_debug = isr_state;
isr_state = isr_state>>8;
protocol = IBMPC_PROTOCOL_XT_CLONE;
goto DONE;
}
}
break;
case 0b11100000:
// XT_IBM-error-done
isr_debug = isr_state;
isr_state = isr_state>>8;
protocol = IBMPC_PROTOCOL_XT_ERROR;
goto DONE;
break;
case 0b10100000: // ^2
{
uint8_t us = 100;
// wait for rising and falling edge of AT stop bit to discriminate between XT and AT
while (!(IBMPC_CLOCK_PIN&(1<<clock_bit)) && us) { wait_us(1); us--; }
while ( IBMPC_CLOCK_PIN&(1<<clock_bit) && us) { wait_us(1); us--; }
if (us) {
// found stop bit: AT-midway - process the stop bit in next ISR
goto NEXT;
} else {
// no stop bit: XT_IBM-done
isr_debug = isr_state;
isr_state = isr_state>>8;
protocol = IBMPC_PROTOCOL_XT_IBM;
goto DONE;
}
}
break;
case 0b00010000:
case 0b10010000:
case 0b01010000:
case 0b11010000:
// AT-done
// TODO: parity check?
isr_debug = isr_state;
// stop bit check
if (isr_state & 0x8000) {
protocol = IBMPC_PROTOCOL_AT;
} else {
// Zenith Z-150 AT(beige/white lable) asserts stop bit as low
// https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#zenith-z-150-beige
protocol = IBMPC_PROTOCOL_AT_Z150;
}
isr_state = isr_state>>6;
goto DONE;
break;
case 0b01100000:
case 0b00110000:
case 0b10110000:
case 0b01110000:
case 0b11110000:
default: // xxxx_oooo(any 1 in low nibble)
// Illegal
isr_debug = isr_state;
error = IBMPC_ERR_ILLEGAL;
goto ERROR;
break;
}
DONE:
// store data
if (!ringbuf_put(&rb, isr_state & 0xFF)) {
// buffer overflow
error = IBMPC_ERR_FULL;
// Disable ISR if buffer is full
int_off();
// inhibit: clock_lo
IBMPC_CLOCK_PORT &= ~(1<<clock_bit);
IBMPC_CLOCK_DDR |= (1<<clock_bit);
}
ERROR:
// clear for next data
isr_state = 0x8000;
NEXT:
return;
}
/* send LED state to keyboard */
void IBMPC::host_set_led(uint8_t led)
{
if (0xFA == host_send(0xED)) {
host_send(led);
}
}
// NOTE: With this ISR data line can be read within 2us after clock falling edge.
// To read data line early as possible:
// write naked ISR with asembly code to read the line and call C func to do other job?
ISR(IBMPC_INT_VECT)
{
IBMPC::interface0.isr();
}
#if defined(IBMPC_CLOCK_BIT1) && defined(IBMPC_DATA_BIT1) && defined(IBMPC_INT_VECT1)
ISR(IBMPC_INT_VECT1)
{
IBMPC::interface1.isr();
}
#endif

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tmk_core/protocol/ibmpc.hpp Normal file
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/*
Copyright 2010,2011,2012,2013,2019 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.
*/
#ifndef IBMPC_HPP
#define IBMPC_HPP
#include <stdbool.h>
#include "wait.h"
#include "ringbuf.h"
/*
* IBM PC keyboard protocol
*
* PS/2 Resources
* --------------
* [1] The PS/2 Mouse/Keyboard Protocol
* http://www.computer-engineering.org/ps2protocol/
* Concise and thorough primer of PS/2 protocol.
*
* [2] Keyboard and Auxiliary Device Controller
* http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
* Signal Timing and Format
*
* [3] Keyboards(101- and 102-key)
* http://www.mcamafia.de/pdf/ibm_hitrc11.pdf
* Keyboard Layout, Scan Code Set, POR, and Commands.
*
* [4] PS/2 Reference Manuals
* http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
* Collection of IBM Personal System/2 documents.
*
* [5] TrackPoint Engineering Specifications for version 3E
* https://web.archive.org/web/20100526161812/http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
*/
#define IBMPC_ACK 0xFA
#define IBMPC_RESEND 0xFE
#define IBMPC_SET_LED 0xED
#define IBMPC_PROTOCOL_NO 0
#define IBMPC_PROTOCOL_AT 0x10
#define IBMPC_PROTOCOL_AT_Z150 0x11
#define IBMPC_PROTOCOL_XT 0x20
#define IBMPC_PROTOCOL_XT_IBM 0x21
#define IBMPC_PROTOCOL_XT_CLONE 0x22
#define IBMPC_PROTOCOL_XT_ERROR 0x23
// Error numbers
#define IBMPC_ERR_NONE 0
#define IBMPC_ERR_RECV 0x00
#define IBMPC_ERR_SEND 0x10
#define IBMPC_ERR_TIMEOUT 0x20
#define IBMPC_ERR_FULL 0x40
#define IBMPC_ERR_ILLEGAL 0x80
#define IBMPC_ERR_FF 0xF0
#define IBMPC_LED_SCROLL_LOCK 0
#define IBMPC_LED_NUM_LOCK 1
#define IBMPC_LED_CAPS_LOCK 2
#define RINGBUF_SIZE 16
class IBMPC
{
public:
static IBMPC interface0;
#if defined(IBMPC_CLOCK_BIT1) && defined(IBMPC_DATA_BIT1)
static IBMPC interface1;
#endif
volatile uint16_t isr_debug;
volatile uint8_t protocol;
volatile uint8_t error;
void host_init(void);
void host_enable(void);
void host_disable(void);
int16_t host_send(uint8_t data);
int16_t host_recv_response(void);
int16_t host_recv(void);
void host_isr_clear(void);
void host_set_led(uint8_t led);
IBMPC() : isr_debug(IBMPC_ERR_NONE), protocol(IBMPC_PROTOCOL_NO), error(IBMPC_ERR_NONE),
isr_state(0x8000), timer_start(0),
clock_bit(IBMPC_CLOCK_BIT), data_bit(IBMPC_DATA_BIT) {
};
IBMPC(uint8_t clock, uint8_t data) : IBMPC() {
clock_bit = clock;
data_bit = data;
}
inline void isr(void) __attribute__((__always_inline__));
private:
volatile uint16_t isr_state;
uint8_t timer_start;
ringbuf_t rb;
uint8_t rbuf[RINGBUF_SIZE];
uint8_t clock_bit, data_bit;
inline void clock_lo(void)
{
IBMPC_CLOCK_PORT &= ~(1<<clock_bit);
IBMPC_CLOCK_DDR |= (1<<clock_bit);
}
inline void clock_hi(void)
{
/* input with pull up */
IBMPC_CLOCK_DDR &= ~(1<<clock_bit);
IBMPC_CLOCK_PORT |= (1<<clock_bit);
}
inline bool clock_in(void)
{
IBMPC_CLOCK_DDR &= ~(1<<clock_bit);
IBMPC_CLOCK_PORT |= (1<<clock_bit);
wait_us(1);
return IBMPC_CLOCK_PIN&(1<<clock_bit);
}
inline void data_lo(void)
{
IBMPC_DATA_PORT &= ~(1<<data_bit);
IBMPC_DATA_DDR |= (1<<data_bit);
}
inline void data_hi(void)
{
/* input with pull up */
IBMPC_DATA_DDR &= ~(1<<data_bit);
IBMPC_DATA_PORT |= (1<<data_bit);
}
inline bool data_in(void)
{
IBMPC_DATA_DDR &= ~(1<<data_bit);
IBMPC_DATA_PORT |= (1<<data_bit);
wait_us(1);
return IBMPC_DATA_PIN&(1<<data_bit);
}
inline uint16_t wait_clock_lo(uint16_t us)
{
while (clock_in() && us) { asm(""); wait_us(1); us--; }
return us;
}
inline uint16_t wait_clock_hi(uint16_t us)
{
while (!clock_in() && us) { asm(""); wait_us(1); us--; }
return us;
}
inline uint16_t wait_data_lo(uint16_t us)
{
while (data_in() && us) { asm(""); wait_us(1); us--; }
return us;
}
inline uint16_t wait_data_hi(uint16_t us)
{
while (!data_in() && us) { asm(""); wait_us(1); us--; }
return us;
}
/* idle state that device can send */
inline void idle(void)
{
clock_hi();
data_hi();
}
/* inhibit device to send(AT), soft reset(XT) */
inline void inhibit(void)
{
clock_lo();
data_hi();
}
/* inhibit device to send(XT) */
inline void inhibit_xt(void)
{
clock_hi();
data_lo();
}
void int_init(void)
{
// interrupt at falling edge
if (clock_bit < 4) {
EICRA |= (0x2 << ((clock_bit&0x3)*2));
} else {
EICRB |= (0x2 << ((clock_bit&0x3)*2));
}
}
void int_on(void)
{
EIFR |= (1 << (clock_bit & 0x7));
EIMSK |= (1 << (clock_bit & 0x7));
}
void int_off(void)
{
EIMSK &= ~(1 << (clock_bit & 0x7));
}
};
#endif