[Coco] Fwd: IP packets on my coco

[Dave Philipsen]

Yeah, that would probably work ok since you've got a relatively large 
buffer that can receive an entire frame without any CPU intervention.



On 6/10/2016 6:36 PM, John W. Linville wrote:
> On Fri, Jun 10, 2016 at 05:27:45PM -0500, Christopher R. Hawks wrote:
>> On Fri, 10 Jun 2016 18:03:22 -0400
>> Brett Gordon <beretta42 at gmail.com> wrote:
>>
>>> The "soft" interrupts (aka polling) that nitros uses is indeed 60 hz.
>>>
>>> Brett M Gordon
>>> On Jun 10, 2016 4:52 PM, "Dave Philipsen" <dave at davebiz.com> wrote:
>>>
>>>> So I have a question since it has been many years since I wrote an
>>>> OS9 device driver.  If the driver is written to poll the device
>>>> instead of being interrupt driven, how often will it poll the
>>>> device to check for the necessity to service it? Once each tick?
>>>>
>>>> Dave Philipsen
>>>>
>>     
>>      So you'd have to (theoretically) process 20,833 byes each poll at 10
>> Mbits/Sec (slowest wired ethernet speed). Slowest WiFi is 11 Mbits/Sec,
>> so add 10%.
>>
>>      I know that actual data transfer speeds are about 1/2 the max, but,
>> that's still a lot of data. Big hardware buffers?
> You probably only have one frame (or a small number) queued-up at
> any given time.  Any MAC worth using will have a filter so you only
> receive frames for your unicast address and any multicast addresses
> (including broadcast) that you have subscribed to receive.
>
> In any case, polling is only relevant when you have nothing else to do.
> Once you know that packets are incoming, you just process them until
> you are done.
>
> John