lpc47s457-ns Standard Microsystems Corp., lpc47s457-ns Datasheet - Page 119

• Manufacturer Part Number: lpc47s457-ns
• Description: Advanced I/o With X-bus Interface
• Manufacturer: Standard Microsystems Corp.

The basic GPIO configuration options are summarized in Table 58.
6.12.4 GPIO OPERATION
The operation of the GPIO ports is illustrated in FIGURE 4.
Note: FIGURE 4 is for illustration purposes only and in not intended to suggest specific implementation details.
Note: When the following functions are selected, the associated GPIO pins have bi-directional functionality: P12,
P16, P17.
When a GPIO port is programmed as an input, reading it through the GPIO data register latches either the inverted or
non-inverted logic value present at the GPIO pin. Writing to a GPIO port that is programmed as an input has no
effect (Table 59).
When a GPIO port is programmed as an output, the logic value or the inverted logic value that has been written into
the GPIO data register is output to the GPIO pin. Reading from a GPIO port that is programmed as an output returns
the last value written to the data register (Table 59).
SMSC LPC47S45x
GPx_nIOW
GPx_nIOR
SD-bit
SELECTED
FUNCTION
GPIO
Data Register
Transparent
D-TYPE
D
Q
GPIO
Bit-n
Q
D
DIRECTION
FIGURE 4 − GPIO FUNCTION ILLUSTRATION
Table 58 − GPIO Configuration Summary
BIT
B0
0
0
1
1
0
1
DATASHEET
POLARITY
Page 119 of 259
BIT
B1
0
1
0
1
Pin is a non-inverted output.
Pin is an inverted output.
Pin is a non-inverted input.
Pin is an inverted input.
GPIO
Configuration
Register bit-1
(Polarity)
DESCRIPTION
GPIO
Configuration
Register bit-0
(Input/Output)
GPIO
PIN
Rev. 08-10-09