HHKB support.

matrix_hhkb.c

@@ -0,0 +1,94 @@
+/*
+ * scan matrix
+ */
+#include <avr/io.h>
+#include <util/delay.h>
+#include "keymap.h"
+#include "matrix.h"
+#include "print.h"
+
+// matrix is active low. (key on: 0/key off: 1)
+//
+// HHKB has no ghost and no bounce.
+// row: HC4051 select input channel(0-8)
+//      PB0, PB1, PB2(A, B, C)
+// col: LS145 select low output line(0-8)
+//      PB3, PB4, PB5, PB6(A, B, C, D)
+//      use D as ENABLE: (enable: 0/unenable: 1)
+// key: KEY: (on: 0/ off:1)
+//      UNKNOWN: unknown whether input or output
+//      PE6,PE7(KEY, UNKNOWN)
+#define COL_ENABLE              (1<<6)
+#define KEY_SELELCT(ROW, COL)   (PORTB = COL_ENABLE|(((COL)&0x07)<<3)|((ROW)&0x07))
+#define KEY_ENABLE              (PORTB &= ~COL_ENABLE)
+#define KEY_UNABLE              (PORTB |=  COL_ENABLE)
+#define KEY_ON                  ((PINE&(1<<6)) ? false : true)
+
+// matrix state buffer
+uint8_t *matrix;
+uint8_t *matrix_prev;
+static uint8_t _matrix0[MATRIX_ROWS];
+static uint8_t _matrix1[MATRIX_ROWS];
+
+
+// this must be called once before matrix_scan.
+void matrix_init(void)
+{
+    // row & col output(PB0-6)
+    DDRB = 0xFF;
+    PORTB = KEY_SELELCT(0, 0);
+    // key input(KEY/VALID)
+    DDRE = 0x3F;
+    PORTE = 0x00;
+
+    // initialize matrix state: all keys off
+    for (int i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0xFF;
+    for (int i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0xFF;
+    matrix = _matrix0;
+    matrix_prev = _matrix1;
+}
+
+uint8_t matrix_scan(void)
+{
+    uint8_t state;
+    uint8_t *tmp;
+
+    tmp = matrix_prev;
+    matrix_prev = matrix;
+    matrix = tmp;
+
+    for (int row = 0; row < MATRIX_ROWS; row++) {
+        for (int col = 0; col < MATRIX_COLS; col++) {
+//print("scan: "); phex(row); phex(col); print("\n");
+            KEY_SELELCT(row, col);
+            _delay_us(50);  // from logic analyzer chart
+            KEY_ENABLE;
+            _delay_us(10);  // from logic analyzer chart
+//print("PINE: "); phex(PINE); print("\n");
+            if (KEY_ON) {
+                matrix[row] &= ~(1<<col);
+            } else {
+                matrix[row] |= (1<<col);
+            }
+            KEY_UNABLE;
+            _delay_us(150);  // from logic analyzer chart
+        }
+    }
+    return 1;
+}
+
+bool matrix_is_modified(void) {
+    for (int i=0; i <MATRIX_ROWS; i++) {
+        if (matrix[i] != matrix_prev[i])
+            return true;
+    }
+    return false;
+}
+
+bool matrix_has_ghost(void) {
+    return false;
+}
+
+bool matrix_has_ghost_in_row(uint8_t row) {
+    return false;
+}