在LINUX上动态运行Console to TTY

We have embebed linux on ARM9 board which is connected to another board by serial line TTY1, no other way to communicate with the ARM9 board (no ethernet no usb), in our normal state application ARM9 board exchange datas with the other board on TTY1. In maintenance mode we want to run console on the ARM9 linux board, so our idea was :We have embebed linux on ARM9 board which is co