Titan SoC
The SPA504G uses the Texas Instruments TNETV1057ZDW processor on a Titan SoC, pictured below.
It is super hard to find a datasheet for this CPU/SoC.SoC; Goodhowever, luck!the boot logs reveal that the CPU operates at 87.5 MHz, and the SoC features 60 KB (61.44 KiB) of memory.
This CPU uses a MIPS instruction set.