On 2018-06-06, IL Ka <[email protected]> wrote: > There is >> com0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo > in your dmesg. > > So, I assume your box reports com port somehow (via ACPI probably)
OpenBSD doesn't use ACPI to find an isa UART, it only looks in the fixed locations compiled in to the kernel. Seeing ns16550a in the output suggests that it did actually find one. > Some boxes may have comport built into chipset but no external cable for it. > I have one, I bought cable separately. It's also possible that the UART is present (as part of a superio chip usually) but it isn't even brought ought to a header on the board. > Another option is to use UART that connects to USB For a system console (with access to DDB etc.) you need a "standard" com port. A standard DOS-compatible one at the usual com1/com2 address are easy. PCI/PCIe *might* be possible in some cases but awkward to setup. USB is not possible.
