Hardware and I/O

What is on the board and how to wire to it, one question per page.

• Which port is which

  The four SMAs, the U.FL sockets, the two USB-C sockets. Trust the silkscreen, not the case.

• Wire something to the JP5 header

  Four free 3.3 V pins, where ground is, and what not to touch.

• Toggle a GPIO pin from Linux

  Read or drive the four free pins from the board or from your PC.

• Make pins follow the transmit samples

  Clocks, triggers and markers locked to the transmitted waveform.

• Write a pin pattern in Python

  A complete program: a clock, a frame pulse and a sync marker on the four pins.

• Control the USER LED

  By default it is lit while a transmitter is live. Change that, or drive it yourself.

• Use an external reference clock

  Move R107 to R109, then feed EXT_CLK within the AD9361's limits.

• Check which reference the radio uses

  Lock bits, a frequency measurement, and xo_correction.

• Find a part on the schematic

  Which PDF to trust, which sheets matter, and the ratings everything is checked against.

Reference

The long pages, with every table and measurement:

• What is on the board: devices, clocks, connectors, supply rails.
• GPIO: the three ways to drive a pin, and the full line map.
• Sample-locked GPIO: the feature, how it is built, what was measured.
• The USER LED: wiring, the tx-active trigger, boot-time defaults.
• Vendor schematic: the schematic's provenance and the datasheet figures.