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Re: [Cbor] [COSE] [Rats] RAM requirements for COSE/CWT

Laurence Lundblade <lgl@island-resort.com> Wed, 23 February 2022 21:37 UTC

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From: Laurence Lundblade <lgl@island-resort.com>
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Date: Wed, 23 Feb 2022 13:36:56 -0800
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Cc: "rats@ietf.org" <rats@ietf.org>, cbor@ietf.org, "cose@ietf.org" <cose@ietf.org>
To: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Cbor] [COSE] [Rats] RAM requirements for COSE/CWT
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> On Feb 23, 2022, at 1:08 PM, Carsten Bormann <cabo@tzi.org> wrote:
>> 
>> Pulling an ldexp library could be a big deal. It could increase code size by a lot.
> 
> Yes. 
> I should probably write some alternative C code that is a couple lines longer but doesn’t need ldexp.
> (But what do you do with the binary32 then?)

I did that with shifts and masks and got a good education about floating point. :-)

https://github.com/laurencelundblade/QCBOR/blob/master/src/ieee754.c

More on the other parts later. Appreciate the discussion.

LL

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