Re: [ts-7000] Avoiding task preemption by Linux kernel

[mike ingle <>]

If you are up to it, then a transaction approach where the kernel talks to the fpga over spi to a queue, and a state machine in the fpga handles the time critical code should work well.

XMOS makes several nice multi-threaded processors, which handle this kind of application very cleanly.  Inexpensive too.  I am using one where I have a state machine on a 20us cycle time which handles all SPI transactions and maintains the system state in one thread, and other threads handling communications...

Regards Mike

On Aug 12, 2011, at 6:04 AM, tourindorian wrote:

 

Hi,

I'm developing an application (C code) on the TS7550 board, using Linux 2.6. I got an issue trying to use continuously the SPI bus for 20ms.
Every 10ms, the communication is interrupted during about 0.5ms. I guess the Kernel scheduler interrupts the process.

Do you have any idea to fix it? Could I change the tick rate of the scheduler so that it is about 50 or 100ms instead of 10ms? Could I prevent the Kernel from preempting the task during that critical section?

Any idea would be useful :-)

Many thanks,

Dorian.

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