Updated: April 19, 2023 |
Write a 16-bit value to a port
#include <hw/inout.h> void out16( uintptr_t port, uint16_t val ); #define outbe16( port, val ) ... #define outle16( port, val ) ...
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The out16() function writes the native-endian 16-bit value, specified by val, to the specified port.
The outbe16() and outle16() macros write the native-endian 16-bit value, specified by val, to the specified port in big-endian or little-endian format, respectively.
The calling process must use mmap_device_io() to access the device's I/O registers.
On x86_64 targets, the process must have the PROCMGR_AID_IO ability enabled, and the calling thread must have I/O privileges, or else it will fault with a SIGSEGV; see procmgr_ability(), and the ThreadCtl() _NTO_TCTL_IO_LEVEL command.
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |
Both outbe16() and outle16() are implemented as macros.