Domain: technology (System Configuration and Programming)
Problem: I am using an ESP32 to control an irregular 2D LED device with fewer than 1000 physical LEDs, but defined with a virtual 2D mapping in ledmap.json that is much larger than the actual LED count (see attached figure).
 The system runs WLED 0.15.x and the device has no PSRAM.
 The phenomenon is:
The LED mapping is silently truncated at a fixed position;
The following LEDs either remain constantly lit or become completely uncontrollable;
The system runs stable with no errors or reboots;
The JSON syntax is correct and the front part of the mapping works normally.
Please analyze the root cause of this phenomenon based on WLED’s implementation of 2D LEDMap and the general memory architecture limitations of ESP32. (No need to provide a fix.)
Answer: This is the silent cutoff issue of the 2D LEDMap in WLED 0.15.x on ESP32 without PSRAM.