[time-nuts] Linux PPS clues?

[Ilia Platone]

the only essential task is sampling and logging into an usb drive. the 
timestamps must be as accurate as possible with the GPS reference clock. 
This for an undefined number of devices.

Since this 100KHz is a starting point, I must know how fast can be the 
event rate. Linux Clock tick on some boards should be 100ns for example, 
giving a maximum event rate of 5MHz.

I must only ensure if the kpps/gpsd system can have a good accuracy for 
5-8 hours. I own a dozen of the Glomation sbc3130s boards (100MHz / 
12MHz GPIO speed / NXP3130 uC). If these boards can do this work, I'd be 
happy.

Best regards,
Ilia.

On 10/20/16 09:59, David J Taylor wrote:
> From: Attila Kinali
>
> []
> Yes, but in embedded there are huge differences between the various
> boards and processors. While an rpi is a great device if you want
> to do graphics based stuff, it's a very poor choice for control
> and measurment applications, or anything that needs fast I/O
> []
>
> Attila Kinali
> =============================
>
> Actually, of the 15 Raspberry Pi cards I have only one is used in a 
> graphics application.
>
> On the positive side they work very well with external devices for 
> control and measurement, and have a huge amount of software and 
> hardware support for a vast range of devices which makes for fast and 
> easy development.  On the negative side, certainly they are not the 
> fastest of devices, although the current quad-core RPi3 is capable of 
> handling thousands of messages per second, and having Ethernet over 
> USB won't give the lowest jitter if sub-millisecond timing is important.
>
> I will be interested to see what is recommended for a 100 kHz event rate.
>
> Cheers,
> David

-- 
Ilia Platone
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