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Re: stdio vs. diag_printf



Grant Edwards <grante@visi.com> writes:
> On Tue, Jul 11, 2000 at 11:33:09AM +0100, Hugo 'NOx' Tyson wrote:
> 
> > But beware: diag_printf is synchronous 
> 
> That's a good thing if you're using the messages to figure out
> if a particular line of code has executed.  ;)

Yup, that's part of the point.
 
> > and disables interrupts for quite a long time.  
> 
> That would be a problem. 
> 
> I can't find the spot where interrupts are disabled in
> daig_printf.  Can you perhaps point me towards the right source
> file?

It tends to be in the individual HAL's diagnostic print routine; ints
aren't off for the whole time of printf processing, but they are off for
the whole time it takes to send a GDB $O packet down the serial
string... (if you're using stubs)

> > Whether this matter depends on your network performance needs...
> 
> I try to keep diagnostic messages small enough to fit in the
> UART's FIFO, so they generally don't "block".  If long messages

Divide by 2.delta for GDB $O formatting...?  But yes, you clearly
understand the issue here.

> start to delay things, I'll crank up the baud rate some more.
> I'm currently running at 57.6K, and can go as high as 460.8K if
> I need to.

<FX: whistles appreciatively>

	- Huge

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