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microsoft / pxt-calliope

A Microsoft MakeCode editor for the Calliope Mini board
https://makecode.calliope.cc
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First random number always the same #255

Open jasperp92 opened 11 months ago

jasperp92 commented 11 months ago

The block "random int" generates the same pseudo random number after reset. It looks like it shows the seed, but has not generated a random number yet.

kreutel commented 11 months ago

Fount that one too. The RNG gets seeded identically every time - or not at all. Anyway: The sequence of random numbers is always the same.

Amerlander commented 11 months ago

I'm working on it. Choosing the calliope mini 1 template should still give random numbers.

Amerlander commented 11 months ago

I'm working on it. Choosing the calliope mini 1 template should still give random numbers.

Sorry, I was talking about the beta version.

Seems related to the bluetooth stack. I Can reproduce it on the microbit when I load ble: https://makecode.microbit.org/S81402-73332-20016-17530 In the beta version bluetooth is only loaded for mini 2 and mini 3 devices, that's why the mini 1 template shows random numbers.

The random seed generation falls back to a static seed if ble is enabled: https://github.com/calliope-edu/codal-microbit-v2/blob/dc0383b581156ef8196202b299a629c6c29d6ba9/source/MicroBitDevice.cpp#L67

Usually, the ubit.init() function should generate the seed before ble actually starts, so that should not be an issue. I also was not able to reproduce this issue using the samples with enabled ble. I also tried to generate a random seed by sensor data when ble is enabled, but this has no effect: https://github.com/calliope-edu/codal-microbit-v2/blob/beed355baa7308c176aeef4ea5e316ddcc74f7a8/model/MicroBit.cpp#L215