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True, but all those are really obsolete Cortex-A cores. The Cortex-M cores used in microcontrollers have a much slower evolution, but the Cortex-A cores are up
by adrian_b 2y ago
True, but all those are really obsolete Cortex-A cores.
The Cortex-M cores used in microcontrollers have a much slower evolution, but the Cortex-A cores are updated every year and the differences between the more recent cores and the older cores are very big.
Cortex-A78, like in MediaTek Genio 1200 is the 2021 Cortex-A core.
Cortex-A76, like in RK3588 and Raspberry Pi 5 is the 2019 Cortex-A core, already 5 years old.
All older Cortex-A cores are hopelessly obsolete.
There still are some borderline acceptable SBCs that use Cortex-A73, the 2017 Cortex-A core, i.e. 7 years old.
The NXP and TI products use much weaker Cortex-A cores than even that.
The only NXP products with Cortex-A cores that can be acceptable for certain purposes are those with Cortex-A55 cores (2018). These at least support the Armv8.2-A ISA, which corrects some important defects in the original Armv8-A instruction set.
Nevertheless, the Cortex-A55 cores are very small and slow, so using a CPU with them is justified only if that results in a much smaller or much cheaper SBC than when using Cortex-A7x cores. That means that any acceptable SBC that uses Cortex-A55 cores must be small and fanless, e.g. a fanless credit-card-sized SBC that must be cheap too, e.g. not exceeding $50 unless it contains a lot of memory and interfaces that could justify a price slightly higher than that.
Many of the solutions using TI or NXP Cortex-A based devices fail to satisfy the power consumption, size and price values that are expected for such cores (frequently due to their use of ancient manufacturing processes, which may make a Cortex-A55 consume as much power as a Cortex-A7x made with a newer CMOS process).
NXP makes microcontrollers with 1 GHz Cortex-M7 cores, which are good enough for many of the applications for which Raspberry Pi SBCs have been used. For the remaining applications, which need fast interfaces, like for SSDs, USB 3 or multiple Ethernet interfaces, it is better to go directly to a SBC like Radxa X4, so there are only very few applications where a device with obsolete Cortex-A cores can be preferred to a either a cheaper microcontroller or a faster Intel Atom CPU.