diff --git a/avr/Makefile b/avr/Makefile
index 459e5fc..778861e 100644
--- a/avr/Makefile
+++ b/avr/Makefile
@@ -15,7 +15,7 @@ OBJCOPY		= $(CROSS)objcopy
 OBJCOPY_FLAGS	= -S
 
 AVRDUDE		= avrdude
-AVRDUDE_DEVICE	= /dev/cu.usbmodem1421
+AVRDUDE_DEVICE	= /dev/ttyACM0
 AVRDUDE_FLAGS	= -c arduino -p atmega328p -b 115200 -D -P $(AVRDUDE_DEVICE)
 
 HEADERS_LOCAL	=
diff --git a/avr/send.c b/avr/send.c
index 0af97cf..ab1fbdb 100644
--- a/avr/send.c
+++ b/avr/send.c
@@ -43,7 +43,7 @@ static void spi_init() {
     /*
      * Set output pins clear by default
      */
-    PORTB &= ~(1 << PORTB4);
+    PORTB &= ~((1 << PORTB5) | (1 << PORTB4));
 }
 
 static uint8_t spi_send_byte(uint8_t value) {
@@ -51,27 +51,27 @@ static uint8_t spi_send_byte(uint8_t value) {
               i = 0;
 
     for (i=0; i<8; i++) {
+        PORTB |= (1 << PORTB5);
+
         if (value & 0x80) {
             PORTB |=  (1 << PORTB4);
         } else {
             PORTB &= ~(1 << PORTB4);
         }
 
-        value <<= 1;
-
-        PORTB |= (1 << PORTB5);
-
-        _delay_us(60);
+        _delay_us(140);
 
         ret <<= 1;
 
-        PORTB &= ~(1 << PORTB5);
-
         if (PINB & (1 << PINB3)) {
             ret |= 1;
         }
 
-        _delay_us(60);
+        PORTB &= ~(1 << PORTB5);
+
+        _delay_us(140);
+
+        value <<= 1;
     }
 
     return ret;
@@ -91,7 +91,9 @@ static void spi_send_packet() {
     (void)spi_send_byte( sum & 0x00ff);
     (void)spi_send_byte((sum & 0xff00) >> 8);
 
-    status = spi_send_byte(0);
+    _delay_us(1200);
+
+    device = spi_send_byte(0);
     status = spi_send_byte(0);
 }