bit7 

 bit6 

bit5

bit4

bit3

bit2

bit1

bit0

 Saturn Peripheral ID 

 0 

 0 

 1 

 1 

 Data size 

 1st Data  

 Right 

 Left 

Down

Up

Start

A TRG

C TRG

B TRG

 2nd Data  

 R TRG 

 X TRG 

Y TRG

Z TRG

L TRG

 Extended data  

 3rd Data  

 0 

 Caps 
 Lock 

Num
Lock

Scrool
Lock

Make

1

1

Break

 4th Data  

 D7 

 D6 

D5

D4

D3

D2

D1

D0

 5th Data  

 Extended data  

 ・ 

 Extended data  

 ・ 

 Extended data  

 nth Data  

 Extended data 

* Right, Left, Down, Up, Start, A TRG, C TRG, B TRG, R TRG, X TRG, Y TRG, Z TRG, L TRG are 0 when the button is pressed.
The correspondence between each button and keyboard key is as follows.

button	key
Right	→
Left	←
Down	↓
Up	↑
Start	ESC
A TRG	Z
C TRG	C
B TRG	X
R TRG	E
X TRG	A
Y TRG	S
Z TRG	D
L TRG	Q

Caps Lock is 1: Caps Lock is locked (Caps Lock LED is lit)
Num Lock is 1: Num Lock is locked (Num Lock LED is lit)
Scroll Lock 1: Scroll Lock is locked (Scroll Lock LED is lit)
∙ Make indicates 1 when there is a valid make code in D7 to D0 (key press indicated by D7 to D0 code).
”Break indicates 1 when there is a valid Break code in D7 to D0 (key press release indicated by D7 to D0 code).
D7 to D0 indicate key numbers. Use with Make and Break.