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Re: ROMRAM application runs much slower than RAM


Platform is based on AT91EB40a. Our clock frequency is different. I have
changed the clock freq and real time clock period settings accordingly.
Yes cache is enabled. When I built the .ecc file for ROMRAM, I copied
the .ecc for RAM startup and used it as my base. and changed the
relevant settings to make it ROMRAM.

Gary Thomas wrote:

On Sun, 2005-02-06 at 01:42 -0800, Harshit Suri wrote:


Hi
I've built an application code both in ROMRAM startup and RAM startup mode.
The code blinks LEDs.

The ROMRAM application runs *significantly* slower than the RAM
version. The time between LEDs blinks is much longer in ROMRAM. I've
generated the delays using 'for' loops like so:

while(1)
{
    LEDs ON;
    for (delay = 0 ; delay <100000;delay++);
    LEDs OFF;
    for (delay = 0 ; delay <100000;delay++);
}

All parameters like clock frequency and RTC settings are same in both.

This puzzles me. Both startup modes finally run from RAM.

Then why this disparity in speeds?
thanks



It's hard to tell with so few details.


What's the target platform?
Are you sure that caches are enabled in the ROMRAM configuration?






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