Re: ARM code size

daniel wrote:
Hi,

I am moving from 8051 to ARM, I have a question related to code size.

In 8051, if code size is about 64K bytes, it should be big enough. However, for ARM(take LPC2214 as example), it has 256k bytes built-in
flash,
because ARM instruction is 32bits word long, so its actually code size 64K
instructions, then my question is 64K instructions code size is enough most
ARM project ? Thanks.

An ARM instruction is capable of doing much more than
an 8051 instruction, so you should need less instructions
for the same task.

If space is a concern, get an ARM with the 'T' (like ARM7TDMI)
and use the Thumb mode. The size is roughly 60% of the equivalent
32-bit ARM code, albeit somewhat slower.

--

Tauno Voipio
tauno voipio (at) iki fi
'
.

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