Is the Apple Watch Series 3 (S3) 64-bit?

zuckk45trfd

macrumors newbie
Original poster
Dec 11, 2017
4
1
Are there developers here? uses the watchOS 4 under 64 bit with the Apple Watch Series 3 or only 32bit?
 

zuckk45trfd

macrumors newbie
Original poster
Dec 11, 2017
4
1
I think the ifixit teardown shows 32 bit.
This is correct with 32 bit, but this is for the eSIM.
ST Microelectronics ST33G1M2 32 bit MCU with ARM SecurCore SC300
https://www.ifixit.com/Teardown/Apple+Watch+Series+3+Teardown/97521


Apple S3 chip has this number - Apple? 339M00035
Here the details missing. 32 bit or 64 bit chip?

series 2 is 64 bit
do you have a link or how do you know?
 
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CobraPA

macrumors 6502a
Mar 12, 2011
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Lansdale, PA, USA
I’m not sure Apple has said. One group that opens up the chips is Chipworks, but it doesn't look like they’ve finished their S2 tear down, let alone the S3. Or maybe they destroyed the S2 and found it too difficult to analyze. You can see their S2 info here: http://www.chipworks.com/ja/node/414 . (The S2 and S3 are custom Apple packages that contain the primary CPU, so unless Apple tells us or someone can analyze the silicon, we're not likely to know.)
 

mike-s

macrumors newbie
Dec 21, 2011
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14
Sorry this is so late but I just ran a test project to check for myself. It is indeed 32 bit. It returned 4 when printing sizeof(void *) which means the memory address space is 4 bytes long which is equal to 32 bits.
 

matrix07

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Jun 24, 2010
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Sorry this is so late but I just ran a test project to check for myself. It is indeed 32 bit. It returned 4 when printing sizeof(void *) which means the memory address space is 4 bytes long which is equal to 32 bits.
Would Apple Watch benefit from being 64 bits?
 

Lennyvalentin

macrumors 65816
Apr 25, 2011
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Would Apple Watch benefit from being 64 bits?
Not really. You could do it just for the sake of it, but it'd be burning power and consuming additional RAM with no advantage to show for it.

64-bit CPUs mainly benefit the two situations; one where you need large memory space/addressing (which isn't the case here; 1st gen Watch had 512MB RAM, not heard that the more recent versions expanded on this), which is easily handled by the 4GB max limit of 32-bit addressing.

The other situation is where you need to be able to process very large numbers quickly; again not really an issue in a smartwatch. Also, there are various maths instruction set extensions that might be able to aid here if large number processing was ever some sort of bottleneck.

64-bit CPUs also have some drawbacks, in that instruction size may go up, making program code less dense/more RAM consuming. Also, 64-bit processing requires more transistors in the CPU, meaning greater cost and higher power consumption.

Better RAM memory?
Having a 64-bit CPU doesn't really make your RAM "better"... :)

Edit: Grammer...
 
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