Run by a timer. No manual interaction. It does not look like a heap problem. The memory looks ok:
> tmr.alarm(1,30000,1,function()print(tmr.time())print(node.readvdd33())print(node.heap())print("------------")end)
> 4185
3369
19432
------------
4215
3370
19432
------------
4244
3369
19432
------------
4274
3368
19432
------------
4304
3368
19432
------------
4334
3367
19432
------------
4363
3369
19432
------------
4393
3368
19432
------------
4423
3369
19432
------------
4452
3370
19432
------------
4482
3369
19432
------------
4512
3369
19432
------------
4542
3368
19432
------------
4571
3369
19432
------------
4601
3369
19432
------------
4631
3370
19432
------------
4660
3369
19432
------------
4690
3369
19432
------------
4720
3368
19432
------------
4749
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NodeMCU 1.0.0 Dude-Edition v0.1 build 20150327 powered by Lua 5.1.4
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