|
|
@ -34,7 +34,7 @@ extern i2c_status_t tca9555_status; |
|
|
|
// All address pins of the tca9555 are connected to the ground |
|
|
|
// | 0 | 1 | 0 | 0 | A2 | A1 | A0 | |
|
|
|
// | 0 | 1 | 0 | 0 | 0 | 0 | 0 | |
|
|
|
#define I2C_ADDR 0b0100000 |
|
|
|
#define I2C_ADDR (0b0100000 << 1) |
|
|
|
|
|
|
|
// Register addresses |
|
|
|
#define IODIRA 0x06 // i/o direction register |
|
|
@ -192,6 +192,7 @@ static matrix_row_t read_cols(uint8_t row) { |
|
|
|
// do nothing |
|
|
|
return 0; |
|
|
|
} else { |
|
|
|
port0 = ~port0; |
|
|
|
// 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. |
|
|
@ -247,7 +248,7 @@ static void select_row(uint8_t row) { |
|
|
|
default: break; |
|
|
|
} |
|
|
|
|
|
|
|
tca9555_status = i2c_writeReg(I2C_ADDR, OREGP1, &port1, 2, I2C_TIMEOUT); |
|
|
|
tca9555_status = i2c_writeReg(I2C_ADDR, OREGP1, &port1, 1, I2C_TIMEOUT); |
|
|
|
// 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. |
|
|
|
} |
|
|
|