diff --git a/avr/send.c b/avr/send.c
index 8109541..eade828 100644
--- a/avr/send.c
+++ b/avr/send.c
@@ -15,7 +15,7 @@ static tabby_printer_packet header = {
 
 static tabby_printer_response response;
 
-static uint8_t body[TABBY_PRINTER_MAX_PACKET_SIZE];
+static uint8_t body[TABBY_PRINTER_PACKET_MAX_SIZE];
 
 static uint16_t sum = 0x0000;
 
diff --git a/include/tabby/avr.h b/include/tabby/avr.h
index 34353c6..1b1d5bb 100644
--- a/include/tabby/avr.h
+++ b/include/tabby/avr.h
@@ -3,6 +3,9 @@
 
 #define SPI_PULSE_USEC 61
 
+/*
+ * SC -- Serial Clock
+ */
 #define SC_DDR      DDRB
 #define SC_DDB      DDB5
 #define SC_PORT     PORTB
@@ -20,6 +23,9 @@
 #define SC_LOW() \
     (SC_PORT &= ~(1 << SC_PORT_PIN))
 
+/*
+ * SI -- Serial In
+ */
 #define SI_DDR      DDRB
 #define SI_DDB      DDB3
 #define SI_PIN_REG  PINB
@@ -36,6 +42,9 @@
 #define SI_IS_HIGH() \
     (SI_PIN_REG & (1 << SI_PIN))
 
+/*
+ * SO -- Serial Out
+ */
 #define SO_DDR      DDRB
 #define SO_DDB      DDB4
 #define SO_PORT     PORTB
diff --git a/include/tabby/printer.h b/include/tabby/printer.h
index 223f6a4..dd55225 100644
--- a/include/tabby/printer.h
+++ b/include/tabby/printer.h
@@ -7,7 +7,7 @@
 #define TABBY_PRINTER_DEVICE_ID 0x81
 #define TABBY_PRINTER_RETRY_COUNT  5
 
-#define TABBY_PRINTER_MAX_PACKET_SIZE 640
+#define TABBY_PRINTER_PACKET_MAX_SIZE 640
 
 #define TABBY_PRINTER_BAND_SIZE  640
 #define TABBY_PRINTER_SHEET_BANDS  9
@@ -56,14 +56,11 @@ typedef struct _tabby_printer_packet {
     };
 } tabby_printer_packet;
 
-typedef struct _tabby_printer_job_packet {
+typedef struct _tabby_printer_buffer {
     tabby_printer_packet header;
-
-    uint8_t sheets,
-            linefeeds,
-            palette,
-            density;
-} tabby_printer_job_packet;
+                 uint8_t body[TABBY_PRINTER_PACKET_MAX_SIZE];
+                uint16_t sum;
+} tabby_printer_buffer;
 
 typedef struct _tabby_printer_response {
     uint8_t device;