Difference between ARM6,ARM7,ARM8
Cheng Yuan-Yuh
I surver ARM's architecture, but the difference, including oragization, instruction set...and so on, between ARM6,ARM7,ARM8 and
other versions confuses me. Could I download documents about this topic from Internet ?
Thanks for any suggestion.
--
Cheng Yuan-Yuh,
E-mail: g87...@oz.nthu.edu.tw
Amanda Richardson
Cheng Yuan-Yuh <g87...@oz.nthu.edu.tw> wrote in message
news:395A2F64...@oz.nthu.edu.tw...
> Hi,
> I surver ARM's architecture, but the difference, including oragization,
instruction set...and so on, between ARM6,ARM7,ARM8 and
> other versions confuses me. Could I download documents about this topic
from Internet ?
This is from memory, so E&OE.
Both ARM6 and ARM7 implement ARM Architecture v.3. The main difference
between these two implementations would be the behaviour under memory abort
conditions. (Historically speaking, ARM Architecture v.2 was implemented by
the ARM2 and ARM3; ARM Architecture v.1 was implemented by the ARM1.)
ARM8 implements v4. This adds new extended multiplies (64-bit results) and
16-bit memory accesses. Again the behaviour under memory abort conditions is
changed.
The processors you're most likely to come across, however, are none of the
above. (The ARM7 is used in some ASSPs, such as the ARM7500 and ARM7500FE,
however.) The ARM7TDMI implements architecture v4T. This is effectively the
same as v4, but adds the Thumb compressed instruction set. This is the core
in the ARM720T and ARM740T cached cores.
This architecture is also implemented by the ARM9TDMI processor core. This
is the core used in the ARM920T and ARM940T products.
The StrongARM implements the same architecture v4 as the ARM8, more-or-less
(the behaviour in certain "unpredictable" areas of the architecture--such
as, for example, specifying a 64-bit multiply with the two destinations the
same register--differs). This is the core used in the Intel SA-110 and
SA-1110 cores.
The ARM9E core implements ARM Architecture v.5TE. This adds a whole range of
DSP instructions and improved instructions for mixed ARM-Thumb programs.
This is the core used in the ARM946E-S and ARM966E-S processors.
Future cores are, well, in the future. Details on them will no doubt emerge
over time.
Mike. (Speaking entirely from memory.)
Michael Hohner
<Ama...@ptoboley.freeserve.co.uk> wrote:
> Future cores are, well, in the future. Details on them will no doubt emerge
> over time.
ARM has already developed and licensed the ARM10 core which has a v5T
instruction set plus VFP instruction set for its floating point unit
(which does not use v4T coprocessor instructions!).
Michael Hohner (m dot hohner at kaneff dot de)
Ing.-Buero Dr. Kaneff
Nuernberg, Germany