Sending data from host to guest on UART

[Mahmoud Shirazi]

Hi,

I am trying to have a connection between the guest and host using UART. The 
guest is uCOSIII and the host is windows 10. The connection has been 
successfully created using COM port. However, the connection is just in one 
direction from guest to host. More precisely, I can send a character from guest 
to host over UART, but, the guest does not receive anything from the host. 
In my implementaion in C, both send and receive are based on interrupts. But, 
when I send a character from host to guest, the interrupt does not raise.
I checked that the interrupt is enable. I guess this is due to Qemu parameters 
or a Qemu bug or ... .
The version of Qemu is 5.2 and also I test with Qemu 6. The machine in xilinx 
zc702 A9. 

Best,
Mahmoud