For NXP (founded by Philips) LPC2131/01 — GPIO Slow Interface, Port 1: 16-Bit
Simulation support for this peripheral or feature is comprised of:
- Dialog boxes which display and allow you to change peripheral configuration.
- VTREGs (Virtual Target Registers) which support I/O with the peripheral.
These simulation capabilities are described below.
GPIO1 Slow Interface (16-bit) Dialog
The General Purpose Input/Output (GPIO) Dialog controls the
direction of the general purpose port pins. You may use the following
controls to select and configure the external interrupt settings.
IOnDIR (Input Output Direction Register) contains
the direction assignments for each I/O port bit. The checkboxes are
checked for output and unchecked for input.
IOnSET (Input Output Set Register) bits are
checked to force a high level for a that port bit during
IOnCLR (Input Output Clear Register) bits are
checked to force a low level for a that port bit during
IOnPIN (Input Output Pin Value Register) contains
the current condition of the GPIO pins.
- Pins is used to manually control a pin value.
Data Type: unsigned long
The PORTx VTREGs represent the I/O pins of the simulated
MCU for Port A, Port B, and so on. PORTA represents Port A, PORTB
represents Port B, etc. You may read PORTx to determine the
state of the output pins of that port. For example, in the command
window you may type,
to obtain value corresponding to the set pins of Port A. You may
also change the input values of port pins by changing the value of
the VTREG. For example,
sets the upper four port pins of Port A to a value of 1 and all
other port pins to a value of 0. You may use the bitwise operators
AND(&), OR(|) and XOR(^) to change individual bits of the PORTx
VTREGs. For example:
PORTA |= 0x00000001; /* Set PA0 Pin */
PORTB &= ~0x00000200; /* Clr PB9 Pin */
PORTA ^= 0x00800000; /* Toggle PA23 Pin */