# CTRDG_SetPhiClock

## Syntax

  `#include <nitro/ctrdg.h>`
  `void CTRDG_SetPhiClock( CTRDGPhiClock clock )`

## Arguments

clock | PHI terminal output control setting

## Return Values

None.

## Description

This function performs PHI terminal output control setting.

The clock argument is in `CTRDGPhiClock` enum format and has the following meanings:

`CTRDG_PHI_CLOCK_LOW` | Low-level output
`CTRDG_PHI_CLOCK_4MHZ` | 4.19MHz clock output
`CTRDG_PHI_CLOCK_8MHZ` | 8.38MHz clock output
`CTRDG_PHI_CLOCK_16MHZ` | 16.76MHz clock output

This function sets both the ARM9 and ARM7.

This function is not thread-safe.

## Internal Operation

Accesses the EXMEMCNT I/O register (0x4000204) of both the ARM9 and ARM7. To do this, it also sends an instruction to the ARM7 via PXI.

## See Also

`CTRDG_GetPhiClock
`

## Revision History

2006/04/28 Changed from MI_ to CTRDG. Revised functionality so that both the ARM7 and ARM9 are set.
2003/12/18 Initial version

CONFIDENTIAL