1 files changed, 94 insertions, 0 deletions
diff --git a/keyboards/xd84/matrix.c b/keyboards/xd84/matrix.c
new file mode 100644
index 000000000..a35905047
--- /dev/null
+++ b/keyboards/xd84/matrix.c
@@ -0,0 +1,94 @@
+/* Copyright 2019
+ *
+ * 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 <stdint.h>
+#include <stdbool.h>
+#include <avr/io.h>
+#include <string.h>
+#include "matrix.h"
+#include "pca9555.h"
+#include "quantum.h"
+
+#include "debug.h"
+
+// PCA9555 slave addresses
+#define IC1 0x20
+#define IC2 0x21
+
+//_____Utility funcs___________________________________________________________
+
+static void init_pins(void) {
+  // init all cols high - IC2 all input
+  pca9555_set_config(IC2, PCA9555_PORT0, ALL_INPUT);//same as initial state
+  pca9555_set_config(IC2, PCA9555_PORT1, ALL_INPUT);//same as initial state
+
+  // init all rows - IC1 port0 input
+  pca9555_set_config(IC1, PCA9555_PORT0, ALL_INPUT);//same as initial state
+}
+
+static void select_row(uint8_t row) {
+  // For the XD84 all rows are on the same IC and port
+  // so its safe enough to assume here row == pin
+  uint8_t pin = row;
+  uint8_t mask = 1 << pin;
+
+  pca9555_set_output(IC1, PCA9555_PORT0, ALL_HIGH & (~mask));
+  pca9555_set_config(IC1, PCA9555_PORT0, ALL_INPUT & (~mask));
+}
+
+static uint16_t read_cols(void) {
+  uint16_t state_1 = pca9555_readPins(IC2, PCA9555_PORT0);
+  uint16_t state_2 = pca9555_readPins(IC2, PCA9555_PORT1);
+
+  // For the XD84 all cols are on the same IC and mapped sequentially
+  // while this technically gives 16 column reads,
+  // the 16th column can never be set so is safely ignored
+  return ~((state_2 << 8) | state_1);
+}
+
+static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
+  // Store last value of row prior to reading
+  matrix_row_t last_row_value = current_matrix[current_row];
+
+  // Clear data in matrix row
+  current_matrix[current_row] = 0;
+
+  // Select row and wait for row selecton to stabilize
+  select_row(current_row);
+  wait_us(30);
+
+  current_matrix[current_row] = read_cols();
+
+  // No need to Unselect row as the next `select_row` will blank everything
+
+  return (last_row_value != current_matrix[current_row]);
+}
+
+//_____CUSTOM MATRIX IMPLEMENTATION____________________________________________________
+
+void custom_matrix_init(void) {
+  pca9555_init(IC1);
+  pca9555_init(IC2);
+
+  init_pins();
+}
+
+bool custom_matrix_scan(matrix_row_t current_matrix[]) {
+  bool changed = false;
+  for (uint8_t current_row = 0; current_row < MATRIX_ROWS; current_row++) {
+    changed |= read_cols_on_row(current_matrix, current_row);
+  }
+  return changed;
+}
+\ No newline at end of file