@@ -178,6 +178,24 @@ Unimplemented features
- Power down mode
- CRC indication
+SPI offload support
+===================
+
+To be able to achieve the maximum sample rate, the driver can be used with the
+`AXI SPI Engine`_ to provide SPI offload support.
+
+.. _AXI SPI Engine: http://analogdevicesinc.github.io/hdl/projects/pulsar_adc/index.html
+
+When SPI offload is being used, some attributes will be different.
+
+* ``trigger`` directory is removed.
+* ``in_voltage0_sampling_frequency`` attribute is added for setting the sample
+ rate.
+* ``in_voltage0_sampling_frequency_available`` attribute is added for querying
+ the max sample rate.
+* ``timestamp`` channel is removed.
+* Buffer data format may be different compared to when offload is not used,
+ e.g. the ``in_voltage0_type`` attribute.
Device buffers
==============