out8s()
Write 8-bit values to a port
Synopsis:
#include <hw/inout.h>
void * out8s( const void * buff,
unsigned len,
uintptr_t port );
Arguments:
- val
- A pointer to a buffer that holds the values that you want to write.
- len
- The number of values that you want to write.
- port
- The port you want to write the values to.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The out8s() function writes len 8-bit values from the buffer pointed to by buff to the specified port.
Returns:
A pointer to the end of the written data.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | Yes |
| Signal handler | Yes |
| Thread | Yes |
Caveats:
The calling thread must have the PROCMGR_AID_IO ability enabled and must have I/O privileges; see procmgr_ability() , and ThreadCtl() 's _NTO_TCTL_IO command for details.
The calling process must also use mmap_device_io() to access the device's I/O registers.
Last modified: 2013-12-23