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ARM-specific Functions

10.4delay.s

This file contains a simple assembly language delay loop, intended to allow time for hardware registers to settle down. The Olicom Ethernet driver uses delay() when programming the registers of the 82595 chip.

The delay() function takes a single argument, the number of microseconds to delay for.

Note

This function is not a precision timing function and the actual time delay will vary with processor clock speed and other hardware-specific variables.

ARM DUI 0079B

Copyright © 1998 and 1999 ARM Limited. All rights reserved.

10-7

ARM-specific Functions

10.5dtrap.s

The function dtrap(), implemented in this file, does nothing. If the RTOS you are using supports a trap to debugger call, you can call that from this function. It is possible to use an armsd.ini file containing the command break @_dtrap to cause the debugger to halt execution of the system when dtrap() is called.

You do not need to include dtrap.s in production code because you will have eliminated all possible causes of dtrap() before production.

10-8

Copyright © 1998 and 1999 ARM Limited. All rights reserved.

ARM DUI 0079B