input (GIN1) during timer INT call

[Linuxbuilders]

Hi Guys,
Is it possible to read input state during a timer int in such way that I don't get "Interrupts disabled during call to prevent re-entrancy" warning?

In short I want to check input state every 50ms unconditionally.
If I do it in main loop then the timing is affected by processors load.

thnx 4 helping.
_________________
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[Ttelmah]

You need to show us what you are doing.

You can read a pin without interrupts being disabled easily. It sounds as if you are in fact calling your own routine to do this. If so, then interrupts will be disabled, and _have_ to be.

So if (for instance) you had to read a device by lowering a CS line, then reading an input pin and then raising the line, and called this in both the main and the interrupt. If you had just dropped the CS, and then the interrupt was called, the interrupt would drop the CS a second time (wouldn't matter), then read the device, and then raise the CS. So you'd arrive back at the read in the main code, with the line high.....

It's all down to what is being done. A simple read, no problem. But anything involving sequencing lines like this, if used both inside and outside the interrupt routines, then interrupts _must_ be disabled, or it isn't going to work....

[Linuxbuilders]

[Ttelmah]

Assuming GIN1, is #defined as a pin number, this won't disable interrupts.

Are you _sure_ this is what is giving the warning?.
Just test with:

[alan]

It occurs when GIN1 is a variable. CCS calls a sub to resolve which pin you are addressing and will thus disable ints if it is used in an interrupt and main.

Regards

[Ttelmah]

Yes.
A person who doesn't keep to the old C standard of reserving ALL CAPITALS for defined values.

As a comment though, assuming a low number of pins involved it'll actually be smaller and faster to just test the value and select the pin.

[Linuxbuilders]