diff --git a/tmk_core/common/keyboard.c b/tmk_core/common/keyboard.c
index eac1f1dd8..93a066e57 100644
--- a/tmk_core/common/keyboard.c
+++ b/tmk_core/common/keyboard.c
@@ -64,20 +64,41 @@ along with this program. If not, see .
#ifdef MATRIX_HAS_GHOST
+static uint16_t matrix_ghost_check[MATRIX_ROWS];
static bool has_ghost_in_row(uint8_t row)
{
- matrix_row_t matrix_row = matrix_get_row(row);
- // No ghost exists when less than 2 keys are down on the row
- if (((matrix_row - 1) & matrix_row) == 0)
+ matrix_row_t matrix_row = (matrix_get_row(row) & matrix_ghost_check[row]);
+ /* No ghost exists when less than 2 keys are down on the row.
+ If there are "active" blanks in the matrix, the key can't be pressed by the user,
+ there is no doubt as to which keys are really being pressed.
+ The ghosts will be ignored, they are KC_NO. */
+ if (((matrix_row - 1) & matrix_row) == 0){
return false;
-
- // Ghost occurs when the row shares column line with other row
+ }
+ // Ghost occurs when the row shares column line with other row, blanks in the matrix don't matter
+ // If there are more than two real keys pressed and they match another row's real keys, the row will be ignored.
for (uint8_t i=0; i < MATRIX_ROWS; i++) {
- if (i != row && (matrix_get_row(i) & matrix_row))
+ if (i != row && __builtin_popcount((matrix_get_row(i) & matrix_ghost_check[i]) & matrix_row) > 1){
return true;
+ }
}
return false;
+ return false;
}
+
+extern const uint8_t keymaps[][MATRIX_ROWS][MATRIX_COLS];
+// bit map of true keys and empty spots in matrix, each row is reversed
+void make_ghost_check_array(){
+ for (int row = 0; row < MATRIX_ROWS; row++) {
+ for (int col = 0; col < MATRIX_COLS; col++) {
+ if (keymaps[0][row][col] & 0xFF)
+ matrix_ghost_check[row] |= 1<