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+FPGA board ports
+================
+
+KC705
+-----
+
+The main target board for the ARTIQ core device is the KC705 development board from Xilinx.
+
+Papilio Pro
+-----------
+
+The low-cost Papilio Pro FPGA board can be used with some limitations.
+
+When plugged to a QC-DAQ LVDS adapter, the AD9858 DDS hardware can be used in addition to a limited number of TTL channels. The TTL lines are mapped to RTIO channels as follows:
+
++--------------+----------+----------------+
+| RTIO channel | TTL line | Capability     |
++==============+==========+================+
+| 0            | PMT0     | Output + input |
++--------------+----------+----------------+
+| 1            | TTL0     | Output only    |
++--------------+----------+----------------+
+| 2            | TTL1     | Output only    |
++--------------+----------+----------------+
+| 3            | TTL2     | Output only    |
++--------------+----------+----------------+