MCP23S17 Microchip Technology, MCP23S17 Datasheet - Page 15

• Manufacturer Part Number: MCP23S17
• Description: 16-Bit I/O Expander with Serial Interface
• Manufacturer: Microchip Technology

1.6.4
The default comparison value is configured in the
DEFVAL register. If enabled (via GPINTEN and
INTCON) to compare against the DEFVAL register, an
opposite value on the associated pin will cause an
interrupt to occur.
REGISTER 1-4:
© 2007 Microchip Technology Inc.
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7-0
R/W-0
DEF7
DEFAULT COMPARE REGISTER
FOR INTERRUPT-ON-CHANGE
DEF7:DEF0: These bits set the compare value for pins configured for interrupt-on-change from
defaults <7:0>. Refer to INTCON.
If the associated pin level is the opposite from the register bit, an interrupt occurs.
Refer to INTCON and GPINTEN.
R/W-0
DEF6
DEFVAL – DEFAULT VALUE REGISTER (ADDR 0x03)
W = Writable bit
‘1’ = Bit is set
R/W-0
DEF5
R/W-0
DEF4
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
MCP23017/MCP23S17
R/W-0
DEF3
R/W-0
DEF2
x = Bit is unknown
R/W-0
DEF1
DS21952B-page 15
R/W-0
DEF0
bit 0