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Re: Re: ARM - AT91 - SPI
Savin Zlobec wrote:
> Sebastian Block wrote:
> >Hi,
> >
> >I think that there is an error in implementation of the function
> >spi_at91_transaction_begin(cyg_spi_device *dev) in spi_at91.c (Line 412)
> >
> > HAL_WRITE_UINT32(AT91_SPI+AT91_SPI_CSR0, val);
> >
> >Using other devices on the spi-bus is not possible.
> >Only the Chip on CS0 is supported, because even if you write to another
> >device-number the generated baudrate and signal mode is only for chip one.
>
> The SPI chip selects are driven manually (bus init sets NPCS pins in IO
> output mode),
> this is needed to satisfy the CS control requirements of SPI bus
> infrastructure. The
> AT91 SPI controller uses only CS0, but the 'outside' world should see
> the requested
> CS active. I only have HW with DataFlash connected to CS0, so I never
> tested this
> driver with devices connected on odher CS.
Ok .. have to try it out how to connect more devices.
but thank you for your explanation.
Sebastian
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