Just exploring about this tp-link XN020-G3v router. I'm mostly interested in connecting to the UART, won't be tinkering with electronics of it, but out of curiosity I tried to search what these chips are. and I couldn't find much about the big chip.
Can anyone describe the 4 main chips on it ? Best would be datasheet, but whatever information you can provide.
I suspect
bigger one(ECONET EN7526FCU) is CPU/SOC, (couldn't find datasheet/specs). Can anyone provide details ?
MT7592N is definitely network IC(found datasheet)
Le9641PQC is network IC. required for VoIP. (found datasheet)
AJ194 (backside) is flash ? How to tinker with it ?
The flash chip is a common 16 MiB SPI NOR flash. An easy way to read or write it would be to use flashrom on a single board computer like a Raspberry Pi.
Unfortunately, that router is not supported by OpenWrt or DD-WRT, so you probably won't be able to do much with it.