165 lines
4.4 KiB
C
165 lines
4.4 KiB
C
/*
|
|
Copyright 2017 Luiz Ribeiro <luizribeiro@gmail.com>
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "matrix.h"
|
|
#include "i2c_master.h"
|
|
|
|
#define RIGHT_HALF
|
|
|
|
|
|
void matrix_set_row_status(uint8_t row);
|
|
|
|
|
|
#if defined(RIGHT_HALF)
|
|
#define I2C_TIMEOUT 10
|
|
#define MCP23018_TWI_ADDRESS 0b0100000
|
|
#define TW_READ 1
|
|
#define TW_WRITE 0
|
|
#define TWI_ADDR_WRITE ( (MCP23018_TWI_ADDRESS<<1) | TW_WRITE )
|
|
#define TWI_ADDR_READ ( (MCP23018_TWI_ADDRESS<<1) | TW_READ )
|
|
#define IODIRA 0x00 // i/o direction register
|
|
#define IODIRB 0x01
|
|
#define IODIRA 0x00 // i/o direction register
|
|
#define IODIRB 0x01
|
|
#define GPPUA 0x0C // GPIO pull-up resistor register
|
|
#define GPPUB 0x0D
|
|
#define GPIOA 0x12 // general purpose i/o port register (write modifies OLAT)
|
|
#define GPIOB 0x13
|
|
#define OLATA 0x14 // output latch register
|
|
#define OLATB 0x15
|
|
#define MCP_ROWS_START 8
|
|
|
|
static uint8_t mcp23018_init(void) {
|
|
uint8_t ret;
|
|
uint8_t data[3];
|
|
// set pin direction
|
|
// - unused : input : 1
|
|
// - input : input : 1
|
|
// - driving : output : 0
|
|
data[0] = IODIRA;
|
|
data[1] = 0b00000000; // IODIRA
|
|
data[2] = (0b11111111); // IODIRB
|
|
|
|
ret = i2c_transmit(TWI_ADDR_WRITE, (uint8_t *)data, 3, I2C_TIMEOUT);
|
|
if (ret) goto out; // make sure we got an ACK
|
|
|
|
// set pull-up
|
|
// - unused : on : 1
|
|
// - input : on : 1
|
|
// - driving : off : 0
|
|
data[0] = GPPUA;
|
|
data[1] = 0b00000000; // IODIRA
|
|
data[2] = (0b11111111); // IODIRB
|
|
|
|
ret = i2c_transmit(TWI_ADDR_WRITE, (uint8_t *)data, 3, I2C_TIMEOUT);
|
|
if (ret) goto out; // make sure we got an ACK
|
|
|
|
// set logical value (doesn't matter on inputs)
|
|
// - unused : hi-Z : 1
|
|
// - input : hi-Z : 1
|
|
// - driving : hi-Z : 1
|
|
data[0] = OLATA;
|
|
data[1] = 0b11111111; // IODIRA
|
|
data[2] = (0b11111111); // IODIRB
|
|
|
|
ret = i2c_transmit(TWI_ADDR_WRITE, (uint8_t *)data, 3, I2C_TIMEOUT);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
void matrix_init_custom(void) {
|
|
// Set rows as output starting high
|
|
DDRB = 0xFF;
|
|
PORTB = 0xFF;
|
|
|
|
// Set columns as inputs with pull-up enabled
|
|
DDRA = 0x00;
|
|
PORTA = 0xFF;
|
|
|
|
// Initialize i2c communication
|
|
i2c_init();
|
|
|
|
#if defined(RIGHT_HALF)
|
|
// Initialize the chip on the other half
|
|
mcp23018_init();
|
|
#endif
|
|
|
|
}
|
|
|
|
static i2c_status_t mcp23018_status = I2C_STATUS_SUCCESS;
|
|
|
|
bool matrix_scan_custom(matrix_row_t current_matrix[]) {
|
|
bool matrix_has_changed = false;
|
|
|
|
#if defined(RIGHT_HALF)
|
|
if (mcp23018_status != I2C_STATUS_SUCCESS) {
|
|
mcp23018_status = mcp23018_init();
|
|
}
|
|
#endif
|
|
|
|
for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
|
|
// Store last value of row prior to reading
|
|
matrix_row_t last_row_value = current_matrix[row];
|
|
|
|
matrix_row_t cols = 0;
|
|
// Select the row to scan
|
|
matrix_set_row_status(row);
|
|
|
|
matrix_io_delay();
|
|
//Set the local row
|
|
|
|
#if defined(RIGHT_HALF)
|
|
// Initialize to 0x7F in case I2C read fails,
|
|
// as 0x75 would be no keys pressed
|
|
uint8_t data = 0x7F;
|
|
// Receive the columns from right half
|
|
if (mcp23018_status == I2C_STATUS_SUCCESS) {
|
|
mcp23018_status = i2c_receive(TWI_ADDR_WRITE, &data, 1, I2C_TIMEOUT);
|
|
}
|
|
#endif
|
|
|
|
cols |= ((~(PINA | 0x80)) & 0x7F);
|
|
#if defined(RIGHT_HALF)
|
|
cols |= (((~(data | 0x80)) & 0x7F) << 7);
|
|
#endif
|
|
|
|
current_matrix[row] = cols;
|
|
matrix_has_changed |= (last_row_value != current_matrix[row]);
|
|
}
|
|
|
|
return matrix_has_changed;
|
|
}
|
|
|
|
void matrix_set_row_status(uint8_t row) {
|
|
#if defined(RIGHT_HALF)
|
|
uint8_t txdata[3];
|
|
|
|
//Set the remote row on port A
|
|
txdata[0] = (GPIOA);
|
|
txdata[1] = ( 0xFF & ~(1<<row) );
|
|
if (mcp23018_status == I2C_STATUS_SUCCESS) {
|
|
mcp23018_status = i2c_transmit(TWI_ADDR_WRITE, (uint8_t *)txdata, 2, I2C_TIMEOUT);
|
|
}
|
|
#endif
|
|
|
|
//Set the local row on port B
|
|
DDRB = (1 << row);
|
|
PORTB = ~(1 << row);
|
|
}
|