MCP23X17EV Microchip Technology, MCP23X17EV Datasheet - Page 5

• Manufacturer Part Number: MCP23X17EV
• Description: BOARD EVAL FOR MCP23X17
• Manufacturer: Microchip Technology

Specifications of MCP23X17EV

• Main Purpose: Interface, GPIO Expander
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP23017, MCP23S17
• Primary Attributes: (2) 16-Bit GPIO Expanders, I2C and SPI
• Secondary Attributes: 4 Momentary Switches, 12 LEDs
• Processor To Be Evaluated: MCP23x17
• Data Bus Width: 16 bit
• Interface Type: SPI
• Silicon Manufacturer: Microchip
• Silicon Core Number: MCP23017, MCP23S17
• Kit Application Type: Interface
• Application Sub Type: GPIO Expander
• Kit Contents: Board
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

INTERNAL ADDRESS POINTER
CONTROL
Some slave serial devices automatically increment
their internal address pointer after each byte is clocked
by the master. This allows the master to sequentially
access multiple registers without re-sending the write
or read command.
Other slave devices do not automatically increment
their internal address pointer.
The MCP23X08/17 family of devices have the ability to
do either by configuring a control bit (IOCON.SEQOP).
This allows maximum flexibility when accessing the
registers.
FIGURE 5:
© 2006 Microchip Technology Inc.
S
0 1 0 0 a
GPIOA
OLATA
IODIRB
IPOLB
IOCON
GPPUB
INTFB
GPIOB
OLATB
INTCAPB
GPINTENB
DEFVALB
INTCONB
MCP23X08
Opcode
a
8-BIT MODE: ADDRESS POINTER DISABLED (MCP23008 EXAMPLE)
a
0 A
0A
1A
09
10
11
12
13
14
15
16
17
18
19
0 0 0 0 1
Addr = 09h
Register
0
1
See Figure 5 and Figure 6 for address pointer examples for the
MCP23X08 8-bit devices and Figure 7 and Figure 8 for the
MCP23X17 examples.
0 A 1 0 1 0 1
When the address pointer is
8-bit mode, the address pointer will not increment the
address pointer.
Data @
09h
0
For example, when configuring the device, it may be
desirable to allow the address pointer to automatically
increment so the device does not have to be re-
addressed after every byte.
Likewise, when performing a continuous operation on
a register (e.g., changing the outputs on a regular basis
by writing to GPIO or OLAT), it may be beneficial to
disable the address incrementing feature so that the
register is always accessed without re-addressing the
register.
1
0 A 0 1 0 1 0
Data @
DISABLED
09h
1
0
1 A 1 0 1 0 1
and the device is in
AN1043
Data @
09h
DS01043A-page 5
0
1
0 P