Peter Fender
New Member
I used a PICAXE 40X2 to drive 208 chasing LEDs for a sign.
The LEDs are mounted on a clear acrylic sheet in the pattern of an EKG heatbeat.
The sheet is mounted on a plywood frame behind a sheet of red acrylic.
A co-worker cut the patterns in the plywood and acrylic with a CNC router.
Notes on the code:
There is extra code to increase the speed in parts of the sign. This may not be needed for other applications.
Sign runs on 3 D-cells, and checks the battery voltage before each sweep. If lower than 3 warning thresholds, it blinks the first LED 1-3 times. Circuit has been running for 2 months now. They usually turn it off at night but sometimes forget.
Only one LED is lit at a time - more will overload current on pins.
Speed is adjustable with the pot.
The push button toggles a slow speed mode used to check the wiring.
If the push button is held down on power-up, it leaves the 1st LED on - used for max current measurement for battery life.
I have a video of the working sign. I'll try to upload separately (too big).
The LEDs are mounted on a clear acrylic sheet in the pattern of an EKG heatbeat.
The sheet is mounted on a plywood frame behind a sheet of red acrylic.
A co-worker cut the patterns in the plywood and acrylic with a CNC router.
Notes on the code:
There is extra code to increase the speed in parts of the sign. This may not be needed for other applications.
Sign runs on 3 D-cells, and checks the battery voltage before each sweep. If lower than 3 warning thresholds, it blinks the first LED 1-3 times. Circuit has been running for 2 months now. They usually turn it off at night but sometimes forget.
Only one LED is lit at a time - more will overload current on pins.
Speed is adjustable with the pot.
The push button toggles a slow speed mode used to check the wiring.
If the push button is held down on power-up, it leaves the 1st LED on - used for max current measurement for battery life.
I have a video of the working sign. I'll try to upload separately (too big).
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