Consider a mesh of nodes:
The nodes may also be connected in sequence:
Details:
How would I submit power from the red node to all the nodes?
On the web, I found many articles about techniques for sending power and data over a single wire. However, those that I looked at don’t fit my particular use case.
So I thought about separating power and data in time. See schematic below. Algorithm, by example:
Disadvantages:
For more information about the project, see my GitHub repo feklee/san.
The nodes may also be connected in sequence:
Details:
- Connector type: coax cables (one signal wire, grounded shielding)
- Connector length: about 10 cm (4 inches)
- Communication speed: currently 4,800 baud (half-duplex, naturally)
- The red node is powered (root node).
- For now: no more than ten nodes
- (Eventually there may be hundreds of nodes.)
How would I submit power from the red node to all the nodes?
On the web, I found many articles about techniques for sending power and data over a single wire. However, those that I looked at don’t fit my particular use case.
So I thought about separating power and data in time. See schematic below. Algorithm, by example:
- Seconds 1-9: Have nodes communicate.
- Second 10: Take data pins off the net, then send a power pulse through the mesh, e.g. 12V. This recharges capacitors.
- Repeat.
Disadvantages:
- untested approach
- wrong timing = fried MCUs
- all nodes need to be in sync (should be doable)
- expensive capacitors needed if not switching often
For more information about the project, see my GitHub repo feklee/san.