Power & Data Status LEDs

Check the Signal. No Laptop Needed.

Three indicators on The Symmetrizer show whether the board has power and what the TTL data line is doing. When a strip stays dark, you see at a glance which side of the cable to check first.

The Symmetrizer board with its indicator LEDs
3 Indicator LEDs
1 Power indicator
2 TTL high / low indicators
0 Tools needed to read them
The Symmetrizer diagram marking the power indicator and the TTL high and low indicators

Indicators

Three LEDs, three answers

The power indicator lights when the board gets its 5–24 V DC supply through the TTL port.

The TTL high and TTL low indicators show the logic level on the TTL data side, so you can see whether a data signal reaches that side of the board.

  • Power indicator: supply present
  • TTL high indicator: data line high
  • TTL low indicator: data line low
Wiring diagram of a 100 m LED line with a differential SPI signal

On Site

Quick checks when a strip stays dark

Most problems on long runs come from wiring and settings, not from the board. The indicators tell you where to start.

  • No power indicator: check the 5–24 V supply and the +POWER and GND wires
  • Power on, but no data activity: check the A/B pair and the direction selector pads
  • With LEC3 or SPI Matrix: make sure "Enable symmetry for LEDs" is switched on and saved in the output settings
  • Data present, pixels flicker: run A and B on one twisted pair, connect unused wires to GND, keep the TTL lead short

FAQ

Status LED questions

That the board receives its 5–24 V DC supply through the +POWER and GND pins of the TTL port.

The logic level on the TTL data side of the board, which tells you whether a data signal is present there.

Check the A/B wiring and the direction selector. With LEC3 or SPI Matrix, also check that "Enable symmetry for LEDs" is on in the output settings. More in Long-Distance SPI Signal.

Troubleshooting a Long Cable Run?

Send us your wiring and settings and our support team will help you find the problem.

Contact Support →