Datasheet

 2005-2016 Microchip Technology Inc. DS20001952C-page 23
MCP23017/MCP23S17
3.5.9 INTERRUPT CAPTURED REGISTER
The INTCAP register captures the GPIO port value at
the time the interrupt occurred. The register is
read-only and is updated only when an interrupt
occurs. The register remains unchanged until the
interrupt is cleared via a read of INTCAP or GPIO.
3.5.10 PORT REGISTER
The GPIO register reflects the value on the port.
Reading from this register reads the port. Writing to this
register modifies the Output Latch (OLAT) register.
REGISTER 3-9: INTCAP: INTERRUPT CAPTURED VALUE FOR PORT REGISTER (ADDR 0x08)
R-x R-x R-x R-x R-x R-x R-x R-x
ICP7 ICP6 ICP5 ICP4 ICP3 ICP2 ICP1 ICP0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ICP<7:0>: Reflects the logic level on the port pins at the time of interrupt due to pin change <7:0>
1 = Logic-high
0 = Logic-low
REGISTER 3-10: GPIO: GENERAL PURPOSE I/O PORT REGISTER (ADDR 0x09)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
GP7 GP6 GP5 GP4 GP3 GP2 GP1 GP0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 GP<7:0>: Reflects the logic level on the pins <7:0>
1 = Logic-high
0 = Logic-low