fixed some memset() and document how to flash firmwares manually

2 files changed, 12 insertions, 2 deletions

diff --git a/README.md b/README.md
index 89f9151..36f36ca 100644
--- a/README.md
+++ b/README.md
@@ -154,6 +154,11 @@ the Reset button on the Teensy 2.0++.
 Once a firmware is running, you can also activate the Teensy Halfkay
 bootloader by pressing LSHIFT+LCTRL+RALT+Pause (LSHIFT+ET1+ET2+PF11 on the K7637.50 layout).
 
+If you would like to flash a firmware with a nonstandard filename, you
+may invoke something like:
+
+    teensy_loader_cli -mmcu=at90usb1286 -w -v k7637_custom_filename.hex
+
 See also: https://github.com/tmk/tmk_keyboard/blob/master/tmk_core/doc/build.md
 
 ## Keymap
diff --git a/matrix.c b/matrix.c
index 7ca3def..5c4ecbd 100644
--- a/matrix.c
+++ b/matrix.c
@@ -63,8 +63,8 @@ void matrix_init(void)
     init_pins();
 
     /* initialize matrix state: all keys off */
-    memset(matrix, sizeof(matrix), 0);
-    memset(matrix_debouncing, sizeof(matrix_debouncing), 0);
+    memset(matrix, 0, sizeof(matrix));
+    memset(matrix_debouncing, 0, sizeof(matrix_debouncing));
 }
 
 /*
@@ -124,6 +124,11 @@ uint8_t matrix_scan(void)
          * key event delivery.
          * When using the buzzer, a short 50ms beep is played every time
          * a new key is pressed.
+         *
+         * FIXME: The Model F solenoids behaved differently.
+         * They retract automatically after a given "Extend time"
+         * (see Model F Technical Reference, p.182).
+         * We should experiment with both methods.
          */
         switch (keyclick_mode) {
             case KEYCLICK_SOLENOID: