adc.readvdd33() on wemos d1 mini pro always gives 65535

[Tuxdiver]

Expected behavior

Calling adc.readvdd33() should return the voltage after setting adc.force_init_mode(adc.INIT_VDD33) and possibly restarting

Actual behavior

Call of adc.readvdd33() always returns 65535, adc.read(0) returns analog value around 7.

Test code

print(adc.force_init_mode(adc.INIT_VDD33))
print(adc.readvdd33())
print(adc.read(0))

gives:

false
65535
7

NodeMCU version

Current own build by docker image:
NodeMCU 2.0.0 build unspecified powered by Lua 5.1.4 on SDK 2.0.0(656edbf)

Hardware

Wemos d1 mini Pro

Possible reason

Could the changed memory layout for modules with more than 4MB flash cause the problem? Maybe the writing to memory position 107 is at the wrong position in the flash?
adc.c:
uint32 init_sector = flash_safe_get_sec_num () - 4;
It does write something, because calling adc.force_init_mode with changing mode returns true in the first call and false after that. But maybe it is not in the right block.

[devsaurus]

Your analysis is most likely correct, thanks for reporting!
Seems I missed this instance - will have a look.

[devsaurus]

@Tuxdiver I was able to reproduce this issue. Fix is contained in the linked PR.

[jmattsson]

Fix merged into dev.