ARM's Cortex CPU core designs are widely used by all kinds of chipmakers who don't want to create their own ARM CPU designs from scratch, so it's important to pay attention when the company announces a new one. The ones we see the most often around here are the mainstream 64-bit cores for smartphones and tablets—the high-end Cortex A72 and A57 and the mid-end Cortex A53—but ARM produces a variety of smaller designs for ultra-low-power and embedded applications, too.
Enter the Cortex A32, a new super-small ARM core designed specifically for wearables, Internet of Things things, embedded systems, low-cost boards like the Raspberry Pi or Pi Zero, and other places where power, space, and cost savings are more important than raw performance. It uses the ARMv8 instruction set and is intended as a replacement for the older Cortex A7 and A5 architectures, both of which use the ARMv7 instruction set. However, the Cortex A32 can only run 32-bit code—to save space and power, the ability to run 64-bit code has been removed.
This is ARM's first CPU with the ARMv8 instruction set that doesn't include 64-bit support. So far, ARMv8 and 64-bit support have gone hand-in-hand. But the new instructions still give the A32 a good performance boost over the Cortex A5 and A7, particularly in cryptography performance. As we've seen in ARMv8-based smartphones, better cryptography performance can drastically reduce the performance hit you take when you encrypt a device's storage. For people who still want 64-bit support, the Cortex A35 CPU core offers similar performance and 64-bit instructions in a slightly larger package (ARM says the A32 is about 10 percent faster than the A35 at 32-bit operations, though, so there's a tradeoff either way).