MPSAFE TTY schedule [uart vs sio]

[Marcel Moolenaar]

On Jul 3, 2008, at 2:09 PM, Sam Leffler wrote:

>> But I just got told sio(4) is required for pc98, because uart(4) is  
>> not
>> supported there. This means I'll seriously consider porting sio(4)  
>> one
>> of these days. It's no biggie, even though I think someone could  
>> better
>> take the effort to extend uart(4).
>>
>
> I would suggest first investigating how difficult it is to port uart  
> to pc98.  Given that we're broadening our platform support having a  
> single serial driver seems preferable.

I looked into it in 2003 but since I don't have any hardware,
I wasn't the one able to do it. I think the fundamental problem
is that the BRG is not part of the UART itself and needs a
separate handle or even (tag, handle) pair to access. That's as
far as I know the only big thing about the work.

For me not having access to the hardware is a showstopper for
looking into it myself.

-- 
Marcel Moolenaar
xcllnt at mac.com