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<H2>SPI Device Driver</H2><p>The SPI kernel device drivers provide access to the BCM2835 spi interface.<p>
<p>In common with many other device drivers it makes 'files' available in the /dev/ folder of your system that you can write to and read from using <B>ioctl</B> commands.</p>
<p>The module <A HREF="mod_device_spi.htm">HiPi::Device::SPI</A> supports communication with SPI devices using the kernel device driver.</p>
<p>The device drivers are configured and loaded at system startup as described in the <A HREF="">Loading Device Drivers Topic.</A></p>
<h3>Allowing None Root Device Permissions</h3>
<p>Users who are members of the group 'spi' can access the SPI devices. By default, user 'pi' is a member of the spi group.</p>
<p>The kernel drivers in Raspbian provide access to the SPI0 peripheral by default. The Raspberry Pi GPIO provides 2 SPI cable select pins and the device driver works by providing a different file for each cable select. You therefore get two device files created for the SPI0 peripheral:</p>
<pre>
/dev/spidev0.0
/dev/spidev0.1
</pre>
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