Hi, i would like to inform others about my problem about complications with serial port.
Firstly i was thinking it is Proxmox related problem, then i realized it does not. So i would like to write up my experience for someone else who will takes same experience as me.
I needed to passthrough rs232 into windows VM for specific application (hardware-PBX). It doesn't work.
1. When i looked in hypervisor as
2. In dmesg i found that the ttyS0/ttyS1 wasnt loaded with driver serial8250. but depends on many other things. In my case i was trying use onboard (Asrock) internal rs232 ports extended to outer.
3. When driver was loaded correctly with playing with grub command line parameters
Because in original that mine computer case was designed as industrial computer. So i did try, doesn't matter. And after replacing that extension cable (ribbon plus slot), then after i had sucess with communication with my device. I'm not sure if DB-9 connector is designed different for rs232 else for rs485. But in my case it worked, so i'm happy.
And about configuration file of virtual machine i used just regular.
In somewhere from begining i was also trying raw qemu args command as
In some days i'll again turn on acpi and will see if serial communication will broke. Because it seems better for me to have it turned on.
So, i would like if my last some days trying to get it work can help someone other.
Thanks.
Edit: i'm using this version
Firstly i was thinking it is Proxmox related problem, then i realized it does not. So i would like to write up my experience for someone else who will takes same experience as me.
I needed to passthrough rs232 into windows VM for specific application (hardware-PBX). It doesn't work.
1. When i looked in hypervisor as
cat /proc/tty/driver/serial i saw many TX but zero RX.2. In dmesg i found that the ttyS0/ttyS1 wasnt loaded with driver serial8250. but depends on many other things. In my case i was trying use onboard (Asrock) internal rs232 ports extended to outer.
3. When driver was loaded correctly with playing with grub command line parameters
apic=noirq or apic=off which are not recommended what i found, then even i still didn't can communicate with device. I red many websites for some advices, but almost nothing was helpful. Then i found some article about ribbon cables and RS232/485, and i was thinking, what if i replace that ribbon cable.Because in original that mine computer case was designed as industrial computer. So i did try, doesn't matter. And after replacing that extension cable (ribbon plus slot), then after i had sucess with communication with my device. I'm not sure if DB-9 connector is designed different for rs232 else for rs485. But in my case it worked, so i'm happy.
And about configuration file of virtual machine i used just regular.
Code:
serial0: /dev/ttyS0
serial1: /dev/ttyS1In somewhere from begining i was also trying raw qemu args command as
args: -chardev serial,id=serial0,path=/dev/ttyS0,logfile=/var/log/ttyS0_vm.log -device isa-serial,chardev=serial0 but it wasnt helpful.In some days i'll again turn on acpi and will see if serial communication will broke. Because it seems better for me to have it turned on.
So, i would like if my last some days trying to get it work can help someone other.
Thanks.
Edit: i'm using this version
pve-manager/7.3-6/723bb6ec (running kernel: 5.15.85-1-pve)
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