Serial TTL router to router strange characters (minicom)

[ZebraOnPC]

I am tring to connect via serial port from one router to another but all i get is

also i have Rapbian on raspberry 3B +
i use minicom on all 3 devices
when i start minicom on raspberry to a router all good
The problem starts when i try to connect via Serial TTL fron one router to an other i get these strange reaction and characters

i have tried change speed but from rasberry to router the paramtrs 115200 8N1 NOR

[mk24]

By default, the OpenWrt kernel takes the serial port to use as a console and also dumps log messages to it. That will interfere with general-purpose usage. The kernel needs to be recompiled to not do that.

[ZebraOnPC]

so there is no way to make serial port on OpenWrt router for using it to connect and manage other ttl devices ?

[Annick]

A little solution : add another adapter USB <-> TTL

[ZebraOnPC]

Thanks a lot I spent 2 days searching for solutions and now I see, so the problem is not a problem it is just openwrt like that?

[ZebraOnPC]

Thanks a lot, I didn't know that