For NXP (founded by Philips) LPC2104 — General Purpose Input/Output (GPIO): 32-Bit Port
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.
General Purpose Input/Output 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.
IODIR (Input Output Direction Register) contains the
direction assignments for each I/O port bit. The checkboxes are
checked for output and unchecked for input.
IOSET (Input Output Set Register) bits are checked to
force a high level for a that port bit during output.
IOCLR (Input Output Clear Register) bits are checked to
force a low level for a that port bit during output.
IOPIN (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 PORT VTREGs represent the I/O pins of the simulated MCU
Port. You may read PORT to determine the state of the output
pins. For example, in the command window you may type,
to obtain the value corresponding to the set pins of the port. 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 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 PORT VTREGs. For
PORT |= 0x00000001; /* Set P0 Pin */
PORT &= ~0x00000200; /* Clr P9 Pin */
PORT ^= 0x00800000; /* Toggle P23 Pin */