Datasheet

MCP23018/MCP23S18

1.6 Configuration and Control

Registers

There are twenty two (22) registers associated with the

MCP23X18 as shown in Table 1-4 and Table 1-5. The

two tables show the register mapping with the two

BANK bit values. Ten (10) registers are associated

with Port A and ten (10) are associated with Port B.

One register (IOCON) is shared between the two ports.

The Port A registers are identical to the Port B regis-

ters, therefore, they will be referred to without differen-

tiating between the port designation (i.e., they will not

have the “A” or “B” designator assigned) in the register

tables.

TABLE 1-4: CONTROL REGISTER SUMMARY (IOCON.BANK = 1)

Name

Address

(hex)

bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

POR/RST

value

IODIRA 00 IO7 IO6 IO5 IO4 IO3 IO2 IO1 IO0 1111 1111

IPOLA 01 IP7 IP6 IP5 IP4 IP3 IP2 IP1 IP0 0000 0000

GPINTENA 02 GPINT7 GPINT6 GPINT5 GPINT4 GPINT3 GPINT2 GPINT1 GPINT0 0000 0000

DEFVALA 03 DEF7 DEF6 DEF5 DEF4 DEF3 DEF2 DEF1 DEF0 0000 0000

INTCONA 04 IOC7 IOC6 IOC5 IOC4 IOC3 IOC2 IOC1 IOC0 0000 0000

IOCON 05 BANK MIRROR SEQOP

— —ODRINTPOLINTCC 0000 0000

GPPUA 06 PU7 PU6 PU5 PU4 PU3 PU2 PU1 PU0 0000 0000

INTFA 07 INT7INT6INT5INT4INT3INT2INT1INTO0000 0000

INTCAPA 08 ICP7 ICP6 ICP5 ICP4 ICP3 ICP2 ICP1 ICP0 0000 0000

GPIOA 09 GP7 GP6 GP5 GP4 GP3 GP2 GP1 GP0 0000 0000

OLATA 0A OL7 OL6 OL5 OL4 OL3 OL2 OL1 OL0 0000 0000

IODIRB 10 IO7 IO6 IO5 IO4 IO3 IO2 IO1 IO0 1111 1111

IPOLB 11 IP7 IP6 IP5 IP4 IP3 IP2 IP1 IP0 0000 0000

GPINTENB 12 GPINT7 GPINT6 GPINT5 GPINT4 GPINT3 GPINT2 GPINT1 GPINT0 0000 0000

DEFVALB 13 DEF7 DEF6 DEF5 DEF4 DEF3 DEF2 DEF1 DEF0 0000 0000

INTCONB 14 IOC7 IOC6 IOC5 IOC4 IOC3 IOC2 IOC1 IOC0 0000 0000

IOCON 15 BANK MIRROR SEQOP — — ODR INTPOL INTCC 0000 0000

GPPUB 16 PU7 PU6 PU5 PU4 PU3 PU2 PU1 PU0 0000 0000

INTFB 17 INT7 INT6 INT5 INT4 INT3 INT2 INT1 INTO 0000 0000

INTCAPB 18 ICP7 ICP6 ICP5 ICP4 ICP3 ICP2 ICP1 ICP0 0000 0000

GPIOB 19 GP7 GP6 GP5 GP4 GP3 GP2 GP1 GP0 0000 0000

OLATB 1A OL7 OL6 OL5 OL4 OL3 OL2 OL1 OL0 0000 0000