qmk_firmware/keyboards/orthodox/serial.c
Art Ortenburger 43579a80a7 add support for Orthodox keyboard (#1436)
* Added orthodox

* Modified readme

* Modified readme

* Modified readme

* Updated makefile

* Fixed keymap issues

* Modified serial communications to allow for over 8 columns

* Fixed sizeof command

* Fixed some typing issues

* Testing issue #1191 (n-column split i2c slave)

Based on initial OrthoDox (serial) config by @reddragond and others,
this attempts to add TWI (I2C) support.
Relevant: <https://github.com/qmk/qmk_firmware/issues/1191>

- per @ahtn recommendation, using memcpy for moving slave matrix
  into slave sending buffer
- slave buffer has been enlarged using sizeof(matrix_row_t)
- note: i2c.h now includes matrix.h
- note: matrix.c includes <string.h>

* Added i2c keymap - right col still not working

* orthodox: re-added i2c keymap, based on serial

* orthodox / issue #1191: trying 9-bit serial

- orthodox serial protocol now sends 9 bits per row, instead of 16.
  Technically it's using MATRIX_COLS, so it might work generically.
- ROW_MASK is #defined in serial.c to truncate the checksums to prevent
  overflows causing false errors. This macro should be renamed if it's
  kept.

* Revert "Fixed sizeof command"

This reverts commit f62a5b9939.

Changes had been made to the lets_split serial driver for testing which
mirrored the multi-byte-row changes made to support the orthodox. As the
lets_split does not require these changes, and new improvements had
been added to the orthodox port only, this commit reverts them.

Because the new code could potentially reduce latency over the serial
transport, it may be desirable to re-add in the future, by backporting
the current working orthodox code.

* orthodox: default serial keymap improvements

- formatting has been improved
- a few keys have been shifted, mainly in Raise and Lower layers,
  to be more like the default Planck layout
- Now available: F12, Home, End, PgUp, PgDn, Media-Next, Media-Play

Still To Do:
- duplicate for TWI
- Alt modifier
- GUI modifier

* orthodox: failed attempt at 16b/row TWI

- duplicated updated serial keymap for "i2c"
- removed string.h/memcpy, instead
- hardcoded copying of six bytes per update
- still doesn't work; master reports interconnect errors on txled

* orthodox: adjusted default keymap

- this is applied to both 'serial' and 'i2c' keymaps
- Alt and GUI have been added, as they were missing
- comma and period persist across more layers; Home/PgUp and End/PgDn
  have been moved slightly to accommodate

* orthodox: revert TWI support to minimum to debug

- disabled ssd1306 and hardware locking in build configuration
- increased TWI buffer from 0x10 to 0x20 bytes
- decreased TWI clock from 400000 to 100000
- removed hardcoded TWI multi-byte sending/receiving

An 'i2c' build of this was found to work on a rev1 Orthodox, although
slave-side col9 was understandably not working. When testing-time
permits, features will be gradually re-enabled towards getting the full
matrix supported over TWI.

* orthodox: TWI (i2c) is working, kludge for col9

The TWI interconnect ("i2c" in directories and build config) is now
working for the Orthodox, including the slave half's column #9.
This is intended as an interim solution, as it's a kludge, not a fix.

Rather than a working multi-byte implementation, the two col9 keys'
bits are packed-into and unpacked-from the two unused bits in row1.
Furthermore, the TWI clock constant has been reduced to 100000 from
400000, as testing revealed the higher value just didn't work.
Testing also found that (with this kludge) increasing the TWI buffer
was not necessary.

This commit leaves many commented-out lines in matrix.c from previous
testing, which will be removed in a future commit once the
interconnects' multi-byte problems have been debugged more thoroughly.

* orthodox: updated readme.md

The readme for the Orthodox now includes a description of the keyboard,
allusions to its author and availability, a linked photo, and links to
the evolving build guide and the current keymap on KLE.
This update has been prepared with /u/Deductivemonkee's assistance.
2017-06-25 21:30:07 -04:00

230 lines
4.9 KiB
C

/*
* WARNING: be careful changing this code, it is very timing dependent
*/
#ifndef F_CPU
#define F_CPU 16000000
#endif
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
#include <stdbool.h>
#include "serial.h"
#ifdef USE_SERIAL
// Serial pulse period in microseconds. Its probably a bad idea to lower this
// value.
#define SERIAL_DELAY 24
matrix_row_t volatile serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH] = {0};
matrix_row_t volatile serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH] = {0};
#define ROW_MASK (((matrix_row_t)0-1)>>(8*sizeof(matrix_row_t)-MATRIX_COLS))
#define SLAVE_DATA_CORRUPT (1<<0)
volatile uint8_t status = 0;
inline static
void serial_delay(void) {
_delay_us(SERIAL_DELAY);
}
inline static
void serial_output(void) {
SERIAL_PIN_DDR |= SERIAL_PIN_MASK;
}
// make the serial pin an input with pull-up resistor
inline static
void serial_input(void) {
SERIAL_PIN_DDR &= ~SERIAL_PIN_MASK;
SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
}
inline static
matrix_row_t serial_read_pin(void) {
return !!(SERIAL_PIN_INPUT & SERIAL_PIN_MASK);
}
inline static
void serial_low(void) {
SERIAL_PIN_PORT &= ~SERIAL_PIN_MASK;
}
inline static
void serial_high(void) {
SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
}
void serial_master_init(void) {
serial_output();
serial_high();
}
void serial_slave_init(void) {
serial_input();
// Enable INT0
EIMSK |= _BV(INT0);
// Trigger on falling edge of INT0
EICRA &= ~(_BV(ISC00) | _BV(ISC01));
}
// Used by the master to synchronize timing with the slave.
static
void sync_recv(void) {
serial_input();
// This shouldn't hang if the slave disconnects because the
// serial line will float to high if the slave does disconnect.
while (!serial_read_pin());
serial_delay();
}
// Used by the slave to send a synchronization signal to the master.
static
void sync_send(void) {
serial_output();
serial_low();
serial_delay();
serial_high();
}
// Reads a byte from the serial line
static
matrix_row_t serial_read_byte(void) {
matrix_row_t byte = 0;
serial_input();
for ( uint8_t i = 0; i < MATRIX_COLS; ++i) {
byte = (byte << 1) | serial_read_pin();
serial_delay();
_delay_us(1);
}
return byte;
}
// Sends a byte with MSB ordering
static
void serial_write_byte(matrix_row_t data) {
matrix_row_t b = MATRIX_COLS;
serial_output();
while( b-- ) {
if(data & (1UL << b)) {
serial_high();
} else {
serial_low();
}
serial_delay();
}
}
// interrupt handle to be used by the slave device
ISR(SERIAL_PIN_INTERRUPT) {
sync_send();
matrix_row_t checksum = 0;
for (int i = 0; i < SERIAL_SLAVE_BUFFER_LENGTH; ++i) {
serial_write_byte(serial_slave_buffer[i]);
sync_send();
checksum += ROW_MASK & serial_slave_buffer[i];
}
serial_write_byte(checksum);
sync_send();
// wait for the sync to finish sending
serial_delay();
// read the middle of pulses
_delay_us(SERIAL_DELAY/2);
matrix_row_t checksum_computed = 0;
for (int i = 0; i < SERIAL_MASTER_BUFFER_LENGTH; ++i) {
serial_master_buffer[i] = serial_read_byte();
sync_send();
checksum_computed += ROW_MASK & serial_master_buffer[i];
}
matrix_row_t checksum_received = serial_read_byte();
sync_send();
serial_input(); // end transaction
if ( checksum_computed != checksum_received ) {
status |= SLAVE_DATA_CORRUPT;
} else {
status &= ~SLAVE_DATA_CORRUPT;
}
}
inline
bool serial_slave_DATA_CORRUPT(void) {
return status & SLAVE_DATA_CORRUPT;
}
// Copies the serial_slave_buffer to the master and sends the
// serial_master_buffer to the slave.
//
// Returns:
// 0 => no error
// 1 => slave did not respond
int serial_update_buffers(void) {
// this code is very time dependent, so we need to disable interrupts
cli();
// signal to the slave that we want to start a transaction
serial_output();
serial_low();
_delay_us(1);
// wait for the slaves response
serial_input();
serial_high();
_delay_us(SERIAL_DELAY);
// check if the slave is present
if (serial_read_pin()) {
// slave failed to pull the line low, assume not present
sei();
return 1;
}
// if the slave is present syncronize with it
sync_recv();
matrix_row_t checksum_computed = 0;
// receive data from the slave
for (int i = 0; i < SERIAL_SLAVE_BUFFER_LENGTH; ++i) {
serial_slave_buffer[i] = serial_read_byte();
sync_recv();
checksum_computed += ROW_MASK & serial_slave_buffer[i];
}
matrix_row_t checksum_received = serial_read_byte();
sync_recv();
if (checksum_computed != checksum_received) {
sei();
return 1;
}
matrix_row_t checksum = 0;
// send data to the slave
for (int i = 0; i < SERIAL_MASTER_BUFFER_LENGTH; ++i) {
serial_write_byte(serial_master_buffer[i]);
sync_recv();
checksum += ROW_MASK & serial_master_buffer[i];
}
serial_write_byte(checksum);
sync_recv();
// always, release the line when not in use
serial_output();
serial_high();
sei();
return 0;
}
#endif