On 22.08.2010 15:45, Tim Jaacks wrote:
> I am using eCos on an LPC2378, running at 72MHz. Some driver I have
> implemented reads out eight double words from a CPU FIFO, using eight
> equal subsequent lines of C-code.
Which FIFO? The UART FIFO is 16 bytes, why 8 DWORDs? In the
case you mean 8 bytes (half a buffer), 8 bytes in 17 us means
3,75 Mbps. I don't know the LPC2378, but as far as I can see
the UART is considered a low-speed interface and is connected
to the APB. Maybe you are stretching the hardware a bit?
> 1. Can anybody explain to me, what eCos is doing within these 12
> microseconds, which the instructions take longer now?
If disabling all interrupts doesn't help I'd guess other activity
on the bus - interrupt being generated and sent to the processor,
maybe DMA, ...
--
Stano
--
Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss
