ColdFire/68K Microcontrollers and ProcessorsのトピックRe: Activating EMAC on MCF5282

Activating EMAC on MCF5282

SVC1 — Tue, 12 Feb 2008 23:54:14 GMT

I am using the M5282EVB and trying the Whetstone benchmark (floating point calculation).

The MCF5282 user's manual states that we can enable/disable the EMAC (Enhanced Multiply Accumulate Unit) by toggling the bit13 of D0 register.

I am executing line by line the example generated automatically by codewarrior (Hello world) and this register changes value very often and bit13 is always 0 (EMAC disabled).

How do I make sure and verify that the EMAC is enabled on the processor?

TIA,

Re: Activating EMAC on MCF5282

stzari — Wed, 13 Feb 2008 20:29:28 GMT

Hi,
the EMAC is always "enabled" on your processor since its an integral part of the MCF5282 CPU.
What you are referring to is the Hardware Configuration Info the CPU writes into D0 after reset. You (usually your debugger, emulator etc.) can read this value to determine which modules are available. The contents of D0 can be safely dismissed after reading (or ignoring) that value.

For further info see Chapter 2.7.14 in the MCF5282 User's Manual

HTH
stzari