1 files changed, 126 insertions, 0 deletions
diff --git a/keyboards/nullbitsco/snap/matrix.c b/keyboards/nullbitsco/snap/matrix.c
new file mode 100644
index 0000000000..ceb9cd8984
--- /dev/null
+++ b/keyboards/nullbitsco/snap/matrix.c
@@ -0,0 +1,126 @@
+/* Copyright 2021 Jay Greco
+ *
+ * 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 <string.h>
+#include "util.h"
+#include "matrix.h"
+#include "split_util.h"
+#include "quantum.h"
+
+#define VIRT_COLS_PER_HAND 1
+#define PHYS_COLS_PER_HAND (MATRIX_COLS - VIRT_COLS_PER_HAND)
+#define ROWS_PER_HAND (MATRIX_ROWS / 2)
+#define COL_SHIFTER ((uint32_t)1)
+#define EXT_PIN_ROW 2
+#define EXT_PIN_COL 8
+
+// Row & column pins
+static uint8_t  row_pins_left[MATRIX_ROWS]      = MATRIX_ROW_PINS;
+static uint8_t  col_pins_left[MATRIX_MUX_COLS]  = MATRIX_COL_MUX_PINS;
+static uint8_t  row_pins_right[MATRIX_ROWS]     = MATRIX_ROW_PINS_RIGHT;
+static uint8_t  col_pins_right[MATRIX_MUX_COLS] = MATRIX_COL_MUX_PINS_RIGHT;
+static uint8_t* row_pins                        = row_pins_left;
+static uint8_t* col_pins                        = col_pins_left;
+
+// Internal functions
+static void init_pins(void) {
+    // Set cols to outputs, low
+    for (uint8_t pin = 0; pin < MATRIX_MUX_COLS; pin++) {
+        setPinOutput(col_pins[pin]);
+    }
+
+    // Unselect cols
+    for (uint8_t bit = 0; bit < MATRIX_MUX_COLS; bit++) {
+        writePinLow(col_pins[bit]);
+    }
+
+    // Set rows to input, pullup
+    for (uint8_t pin = 0; pin < ROWS_PER_HAND; pin++) {
+        setPinInputHigh(row_pins[pin]);
+    }
+
+    // Set extended pin (only on right side)
+    if (!isLeftHand) {
+        // Set extended pin to input, pullup
+        setPinInputHigh(MATRIX_EXT_PIN_RIGHT);
+    }
+}
+
+static void select_col(uint8_t col) {
+    // Drive demux with correct column address
+    for (uint8_t bit = 0; bit < MATRIX_MUX_COLS; bit++) {
+        uint8_t state = (col & (0b1 << bit)) >> bit;
+        writePin(col_pins[bit], !state);
+    }
+}
+
+static void read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
+    select_col(current_col % PHYS_COLS_PER_HAND);
+    wait_us(5);
+
+    // Read each row sequentially
+    for (uint8_t row_index = 0; row_index < ROWS_PER_HAND; row_index++) {
+        if (readPin(row_pins[row_index]) == 0) {
+            current_matrix[row_index] |= (COL_SHIFTER << current_col);
+        } else {
+            current_matrix[row_index] &= ~(COL_SHIFTER << current_col);
+        }
+    }
+}
+
+static void read_ext_pin(matrix_row_t current_matrix[]) {
+    // Read the state of the extended matrix pin
+    if (!isLeftHand) {
+        if (readPin(MATRIX_EXT_PIN_RIGHT) == 0) {
+            current_matrix[EXT_PIN_ROW] |= (COL_SHIFTER << EXT_PIN_COL);
+        } else {
+            current_matrix[EXT_PIN_ROW] &= ~(COL_SHIFTER << EXT_PIN_COL);
+        }
+    }
+}
+
+void matrix_init_custom(void) {
+    if (!isLeftHand) {
+        row_pins = row_pins_right;
+        col_pins = col_pins_right;
+    }
+
+    init_pins();
+}
+
+bool matrix_scan_custom(matrix_row_t current_matrix[]) {
+    matrix_row_t last_matrix[MATRIX_ROWS];
+    memcpy(last_matrix, current_matrix, sizeof(last_matrix));
+
+    #ifdef DEBUG_SLOW_MATRIX
+    // Slow for debugging
+    wait_ms(1000);
+    #endif
+
+    // Set col, read rows
+    for (uint8_t current_col = 0; current_col < PHYS_COLS_PER_HAND; current_col++) {
+        read_rows_on_col(current_matrix, current_col);
+    }
+
+    // Read extended pin and store in matrix
+    read_ext_pin(current_matrix);
+
+    // Check if the matrix changed
+    bool changed = memcmp(last_matrix, current_matrix, sizeof(last_matrix)) != 0;
+
+    return changed;
+}