Wiring and cable diagram

Cable documentation is fiddly and error-prone by hand, and WireViz was built for exactly this: describe connectors, wires and connections in text, and get a correct harness drawing with a bill of materials.

Because it is generated, the diagram and the pinout cannot disagree.

#When to reach for one

Harness and loom documentation for hardware products.
Field service documentation where the pinout is the instruction.
Test rigs and lab setups that somebody else will have to rebuild.

#How to draw it in Capable

Route	Use when
WireViz	Generated harness drawings with pinouts and a parts list.
draw.io	Simple point-to-point wiring where generation is overkill.

#A worked example

A three-wire harness with a real pinout:

The source, which you can paste into a new diagram and edit:

connectors:
  X1:
    type: D-Sub
    subtype: female
    pinlabels: [DCD, RX, TX, GND]
  X2:
    type: Molex KK 254
    subtype: female
    pinlabels: [VCC, RX, TX, GND]

cables:
  W1:
    gauge: 24 AWG
    length: 0.3
    colors: [WH, BN, GN]

connections:
  -
    - X1: [2,3,4]
    - W1: [1,2,3]
    - X2: [2,3,4]

#A few things that catch people out

Wire colours in the diagram must match the wire colours in the box. Generate from one source.
Include gauge and length; they are the two facts a person building it needs.
Pin numbering direction matters. Say whether you are looking at the front or the rear of the connector.

Digital timing diagram

Waveforms, clocks and bus transitions.

HDL block diagram

Component symbols generated from your HDL.

Examples

Working diagrams you can copy.

Approximately right is wrong here.