Datasheet

MCP23009/MCP23S09
DS22121B-page 8 © 2009 Microchip Technology Inc.
FIGURE 1-1: MCP23009 I
2
C™ DEVICE PROTOCOL
S
P
SR
w
R
OP
ADDR
DOUT
DIN
- Start
- Restart
- Stop
- Write
- Read
- Device opcode
- Device address
- Data out from MCP23009
- Data in to MCP23009
S
P
SR
W
R
OP ADDR
DIN DIN
....
S
P
W
R
OP
ADDR
DOUT
DOUT
....
P
SR WOP
ADDR
DIN
....
P
P
SR R
DOUT DOUT
....
P
OP
DOUT
DOUT
....
P
SR OP
DOUT
....
P
OP
DIN
S PWOP ADDR
DIN DIN
....
Byte and Sequential Write
S W OP SR R OP
DOUT DOUT
....
P
Byte and Sequential Read
S WOP ADDR
DIN
P
S WOP SR ROP
DOUT
P
Byte
Sequential
Byte
Sequential
ADDR
ADDR