PortInOut
Use the PortInOut interface to read and write an underlying GPIO port as one value. This is much faster than BusInOut because you can write a port all at once, but it is much less flexible because you are constrained by the port and bit layout of the underlying GPIO ports.
A mask can be supplied so you only use certain parts of a port, allowing other bits to be used for other interfaces.
PortInOut class reference
| Public Member Functions | |
| PortInOut (PortName port, int mask=0xFFFFFFFF) | |
| Create an PortInOut, connected to the specified port. More... | |
| void | write (int value) |
| Write the value to the output port. More... | |
| int | read () |
| Read the value currently output on the port. More... | |
| void | output () |
| Set as an output. More... | |
| void | input () |
| Set as an input. More... | |
| void | mode (PinMode mode) |
| Set the input pin mode. More... | |
| PortInOut & | operator= (int value) |
| A shorthand for write() More... | |
| PortInOut & | operator= (PortInOut &rhs) |
| A shorthand for write() More... | |
| operator int () | |
| A shorthand for read() More... | |
PortInOut hello, world
/*
* Copyright (c) 2020 Arm Limited and affiliates.
* SPDX-License-Identifier: Apache-2.0
*/
#include "mbed.h"
// Switch on an LED if any of mbed pins 21-26 is high
PortIn p(PortA, 0x0000003F); // p21-p26
DigitalOut ind(LED_RED);
int main()
{
while (1) {
int pins = p.read();
if (pins) {
ind = 1;
} else {
ind = 0;
}
}
}
Related content
- BusInOut API reference.