Re: Can I use DOSEMU for testing device driver code?

[Stas Sergeev <stsp@aknet.ru>]

Hello.

Ryan Underwood wrote:
>> The problem in (B) seems to be that all of my transmitted characters
>> disappear into a sort of 'virtual' UART to be transmitted later, whilst
>> the RTS signal seems to come out of the port in 'real' time. 
>  I don't think that is happening. i.e. in,out instructions are directly
>  executed, there is no emulation involved.
No, the "problem B" was about an
emulated access, which is indeed
going via an emulated UART.
Its latency was considerably
reduced in dosemu-1.2.0 (not in
any 1.1), but still of course can't
match the direct access.
The fact that RTS gets out of sync
with the TX looks like a bug, most
likely the emulated FIFO is being
switched on when it shouldn't. But
sigh, looks like that bug will have
to wait for the next time:)
Btw, from the docs I have, it is
unclear whether there are some
ways to disable the FIFO, other than
by writing to FCR directly. But I
strongly suspect that at least
changing the DLAB state also should
disables it, which may explain this
problem.
If someone have an info on that -
would be nice to have a look.