Apple Macs Move to ARM Processors

Introduction

I watched Apple’s introduction of their new Mac computers based on Apple Silicon which contain ARM CPUs. Of course I was excited about this since I wrote two books on ARM Assembly Language Programming. ARM processors are used in nearly all cell phones and tablets. They are used in single board computers like the Raspberry Pi as well as many IoT devices. Finally it looks like we are getting a good line of computers based on ARM processors. In this article we’ll look at why this is a good thing, as well as some of the hurdles that Apple will need to jump for this to be a success.

A Bit of History

The first Macs contained Motorola 68000 series CPUs, then Apple moved to IBM’s PowerPC chips and then on to using Intel CPUs like all other PCs. The Motorola 68000 was a CISC CPU that competed with Intel in the early days to be the heart of the PC. Intel won the race and Motorola lost interest in spending the billions that were required to keep this line of processors competitive. Apple made the decision to jump to IBM’s new RISC based PowerPC platform. Initially this was quite successful, but again IBM didn’t think it was worth investing the money required to keep up with Intel. Intel was competing fiercely against AMD to maintain a lead in processor technology and this battle between Intel and AMD left IBM in their dust. Apple saw the writing on the wall and moved the Mac line of computers to Intel processors.

Advance a few years, and the battle has moved to cell phones. Cell phones all use ARM processors mainly due to their lower power requirements. Now there is a furious battle between the various ARM chip makers to have the faster cell phone. Now the tables have turned and Intel is being left in the dust as its chips are getting older and it is having trouble competing. This gives Apple the chance to move to faster ARM processors that use less power (hence longer battery life) with the added advantage that all their devices from watches to phones to tablets to laptops to desktops all use variations of the same ARM processor.

The Apple M1 Processor

With these new ARM based Apple Macs, Apple introduced their new Apple M1 System on a Chip (SoC). This SoC contains eight ARM CPU cores, 4 are high power units, and 4 are lower power. The new MacOS dispatches threads based on whether they need to save power or maximize performance. This chip incorporates the CPU, GPU and memory all into one chip. The main downside of this is that this will be the least upgradeable Mac yet. I would recommend getting a higher configuration since you won’t be able to add to it down the road.

This is an impressive chip that Apple claims will be competitive with Intel i9 processors. It will be interesting to see the real benchmarks when these computers actually ship next week.

Unified Software

Now that iOS and MacOS programs use the same processor, it makes writing applications that run on everything from watches and phones to laptops and desktop easier. If you need some Assembly language optimizations, now you only need to include the same ARM code for all of them. It’s really cool that you can now run iPhone and iPad apps on your Mac.

Downsides

There are a couple of downsides to this approach, one is the lack up upgradeability due to the memory being included on the CPU chip. Another is that all software needs to be recompiled for the ARM processor. Apple has made this as easy as possible, so hopefully all the main software packages will be updated with ARM versions.

Even if a software vendor doesn’t do this (perhaps they went out of business), these new Macs claim they can run the software anyway by using an Intel emulator called Rosetta. We’ll have to get some real feedback on how well this works, but Apple claims it runs Intel programs better than only slightly older Intel processors.

The other headwind with Apple products is the price. These are higher end products that compete with Microsoft Surface and higher end Dell models. However there are a lot of much cheaper laptops from vendors like Acer or HP. I purchased a MacBook Air in 2012 and it is still going strong, a very solid laptop. The Sunshine Coast Tech Hub maintains half a dozen 2008 MacBook Pros that we use for an Arduino kids coding camp and all these laptops are going strong (admittedly upgraded to SSD drives and running Linux Mint). The price of these new ARM laptops are the same as the previous equivalent Intel models and my experience with Apple products is that they do last.

Will Microsoft and Others Follow?

ARM has released their Cortex A78C CPU that is an 8 core CPU for laptops and desktops where all 8 cores are high performance. How many other hardware vendors will try releasing laptops and desktops based on this chip? Linux runs fine on ARM CPUs, just look at the Raspberry Pi or nVidia Jetson Nano. Microsoft has a simplified version of Windows, similar to ChromeOS for ARM laptops. Will Microsoft support the full Windows Home and Pro on ARM? It will be interesting to see what new devices get released in 2021.

Summary

I’m excited about the new ARM based Apple Macs. If you want to learn more about the ARM CPU, check out one of my books on ARM Assembly Language programming such as the one pictured below. It will be interesting to see how these sell compared to Intel/AMD computers and how many other vendors choose to support ARM CPUs in laptops and desktops in 2021.