/* Copyright 2013 Oleg Kostyuk 2020 Pierre Chevalier 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 . */ /* * This code was heavily inspired by the ergodox_ez keymap, and modernized * to take advantage of the quantum.h microcontroller agnostics gpio control * abstractions and use the macros defined in config.h for the wiring as opposed * to repeating that information all over the place. */ #include "matrix.h" #include "debug.h" #include "wait.h" #include "i2c_master.h" extern i2c_status_t mcp23017_status; #define I2C_TIMEOUT 1000 // For a better understanding of the i2c protocol, this is a good read: // https://www.robot-electronics.co.uk/i2c-tutorial // I2C address: // See the datasheet, section 3.3.1 on addressing I2C devices and figure 3-6 for an // illustration // http://ww1.microchip.com/downloads/en/devicedoc/20001952c.pdf // All address pins of the mcp23017 are connected to the ground on the ferris // | 0 | 1 | 0 | 0 | A2 | A1 | A0 | // | 0 | 1 | 0 | 0 | 0 | 0 | 0 | #define I2C_ADDR 0b0100000 #define I2C_ADDR_WRITE ((I2C_ADDR << 1) | I2C_WRITE) #define I2C_ADDR_READ ((I2C_ADDR << 1) | I2C_READ) // Register addresses // See https://github.com/adafruit/Adafruit-MCP23017-Arduino-Library/blob/master/Adafruit_MCP23017.h #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 bool i2c_initialized = 0; i2c_status_t mcp23017_status = I2C_ADDR; uint8_t init_mcp23017(void) { print("starting init"); mcp23017_status = I2C_ADDR; // I2C subsystem if (i2c_initialized == 0) { i2c_init(); // on pins D(1,0) i2c_initialized = true; wait_ms(I2C_TIMEOUT); } // set pin direction // - unused : input : 1 // - input : input : 1 // - driving : output : 0 // This means: we will read all the bits on GPIOA // This means: we will write to the pins 0-4 on GPIOB (in select_rows) uint8_t buf[] = {IODIRA, 0b11111111, 0b11110000}; mcp23017_status = i2c_transmit(I2C_ADDR_WRITE, buf, sizeof(buf), I2C_TIMEOUT); if (!mcp23017_status) { // set pull-up // - unused : on : 1 // - input : on : 1 // - driving : off : 0 // This means: we will read all the bits on GPIOA // This means: we will write to the pins 0-4 on GPIOB (in select_rows) uint8_t pullup_buf[] = {GPPUA, 0b11111111, 0b11110000}; mcp23017_status = i2c_transmit(I2C_ADDR_WRITE, pullup_buf, sizeof(pullup_buf), I2C_TIMEOUT); } return mcp23017_status; } /* matrix state(1:on, 0:off) */ static matrix_row_t matrix[MATRIX_ROWS]; // debounced values static matrix_row_t read_cols(uint8_t row); static void init_cols(void); static void unselect_rows(void); static void select_row(uint8_t row); static uint8_t mcp23017_reset_loop; void matrix_init_custom(void) { // initialize row and col mcp23017_status = init_mcp23017(); unselect_rows(); init_cols(); // initialize matrix state: all keys off for (uint8_t i = 0; i < MATRIX_ROWS; i++) { matrix[i] = 0; } } void matrix_power_up(void) { mcp23017_status = init_mcp23017(); unselect_rows(); init_cols(); // initialize matrix state: all keys off for (uint8_t i = 0; i < MATRIX_ROWS; i++) { matrix[i] = 0; } } // Reads and stores a row, returning // whether a change occurred. static inline bool store_matrix_row(matrix_row_t current_matrix[], uint8_t index) { matrix_row_t temp = read_cols(index); if (current_matrix[index] != temp) { current_matrix[index] = temp; return true; } return false; } bool matrix_scan_custom(matrix_row_t current_matrix[]) { if (mcp23017_status) { // if there was an error if (++mcp23017_reset_loop == 0) { // if (++mcp23017_reset_loop >= 1300) { // since mcp23017_reset_loop is 8 bit - we'll try to reset once in 255 matrix scans // this will be approx bit more frequent than once per second dprint("trying to reset mcp23017\n"); mcp23017_status = init_mcp23017(); if (mcp23017_status) { dprint("right side not responding\n"); } else { dprint("right side attached\n"); } } } bool changed = false; for (uint8_t i = 0; i < MATRIX_ROWS_PER_SIDE; i++) { // select rows from left and right hands uint8_t left_index = i; uint8_t right_index = i + MATRIX_ROWS_PER_SIDE; select_row(left_index); select_row(right_index); // we don't need a 30us delay anymore, because selecting a // left-hand row requires more than 30us for i2c. changed |= store_matrix_row(current_matrix, left_index); changed |= store_matrix_row(current_matrix, right_index); unselect_rows(); } return changed; } static void init_cols(void) { // init on mcp23017 // not needed, already done as part of init_mcp23017() // init on mcu pin_t matrix_col_pins_mcu[MATRIX_COLS_PER_SIDE] = MATRIX_COL_PINS_MCU; for (int pin_index = 0; pin_index < MATRIX_COLS_PER_SIDE; pin_index++) { pin_t pin = matrix_col_pins_mcu[pin_index]; gpio_set_pin_input(pin); gpio_write_pin_high(pin); } } static matrix_row_t read_cols(uint8_t row) { if (row < MATRIX_ROWS_PER_SIDE) { pin_t matrix_col_pins_mcu[MATRIX_COLS_PER_SIDE] = MATRIX_COL_PINS_MCU; matrix_row_t current_row_value = 0; // For each col... for (uint8_t col_index = 0; col_index < MATRIX_COLS_PER_SIDE; col_index++) { // Select the col pin to read (active low) uint8_t pin_state = gpio_read_pin(matrix_col_pins_mcu[col_index]); // Populate the matrix row with the state of the col pin current_row_value |= pin_state ? 0 : (MATRIX_ROW_SHIFTER << col_index); } return current_row_value; } else { if (mcp23017_status) { // if there was an error return 0; } else { uint8_t buf[] = {GPIOA}; mcp23017_status = i2c_transmit(I2C_ADDR_WRITE, buf, sizeof(buf), I2C_TIMEOUT); // We read all the pins on GPIOA. // The initial state was all ones and any depressed key at a given column for the currently selected row will have its bit flipped to zero. // The return value is a row as represented in the generic matrix code were the rightmost bits represent the lower columns and zeroes represent non-depressed keys while ones represent depressed keys. // Since the pins connected to eact columns are sequential, and counting from zero up (col 5 -> GPIOA0, col 6 -> GPIOA1 and so on), the only transformation needed is a bitwise not to swap all zeroes and ones. uint8_t data[] = {0}; if (!mcp23017_status) { mcp23017_status = i2c_receive(I2C_ADDR_READ, data, sizeof(data), I2C_TIMEOUT); data[0] = ~(data[0]); } return data[0]; } } } static void unselect_rows(void) { // no need to unselect on mcp23017, because the select step sets all // the other row bits high, and it's not changing to a different // direction // unselect rows on microcontroller pin_t matrix_row_pins_mcu[MATRIX_ROWS_PER_SIDE] = MATRIX_ROW_PINS_MCU; for (int pin_index = 0; pin_index < MATRIX_ROWS_PER_SIDE; pin_index++) { pin_t pin = matrix_row_pins_mcu[pin_index]; gpio_set_pin_input(pin); gpio_write_pin_low(pin); } } static void select_row(uint8_t row) { if (row < MATRIX_ROWS_PER_SIDE) { // select on atmega32u4 pin_t matrix_row_pins_mcu[MATRIX_ROWS_PER_SIDE] = MATRIX_ROW_PINS_MCU; pin_t pin = matrix_row_pins_mcu[row]; gpio_set_pin_output(pin); gpio_write_pin_low(pin); } else { // select on mcp23017 if (mcp23017_status) { // if there was an error // do nothing } else { // Select the desired row by writing a byte for the entire GPIOB bus where only the bit representing the row we want to select is a zero (write instruction) and every other bit is a one. // Note that the row - MATRIX_ROWS_PER_SIDE reflects the fact that being on the right hand, the columns are numbered from MATRIX_ROWS_PER_SIDE to MATRIX_ROWS, but the pins we want to write to are indexed from zero up on the GPIOB bus. uint8_t buf[] = {GPIOB, 0xFF & ~(1 << (row - MATRIX_ROWS_PER_SIDE))}; mcp23017_status = i2c_transmit(I2C_ADDR_WRITE, buf, sizeof(buf), I2C_TIMEOUT); } } }