4-Plus-1 CPU

Hi,

I’m curious as to what type of core the “plus 1” core is.

I’ve seen some schematics that say arm7 (http://linuxgizmos.com/nvidia-jetson-tk1-most-advanced-hacker-sbc/), whereas some other website claims it’s still Cortex-A15 (http://elinux.org/Tegra/JetsonTK1_Power).

Also, if it’s an arm7 core it’s probably not running armv7 ISA.
In that case, how does the OS work over two different types of ISA?
Is it just running in THUMB mode on both types of cores?

Anybody have a definitive answer on this?

Thank you.

It’s always been reported in the media as a Cortex-A15.

http://www.anandtech.com/show/7622/nvidia-tegra-k1