Hi I am emulating a UART serial device with QEMU. the guest OS can print to the serial port without a problem. but how can i write to the UART serial port. I tried to use the -serial pty backend and did not work.
i.e. xintong1@fxilab139:$ echo 1 > /dev/pts/21 does not raise an interrupt in the emulated processor. I modified the emulator to print all raised interrupts. The OS i am working on is rather small and have no network capabilities. so serial UART is my only option for now. Xin