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Old 13 January 2021, 11:30   #1
Waxhead
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Join Date: Nov 2020
Location: Etne / Norway
Posts: 9
Bug: Reading from address $BFE400 and $BFE500 always returns 255

Howdy,

Ages ago it seems I made a little program that needed some random numbers. Being a young and stupid programmer I pulled the randomness by reading a char/byte from address $BFE400 and $BFE500 and multiplied those together.

My program used to work on WinUAE but suddenly my program failed. Apparently WinUAE changed something, I can't remember when (but can probably try to find out if needed).

Real Amigas return "noise" by reading these addresses e.g. a random number. fs-uae (and the last time I checked WinUAE) does not. Since UAE strives to be accurate (CPU cycle accurate for example) then in the name of accuracy for the emulation UAE should at least return some pseudo random number to mimmic real Amigas if a read is done on those addresses.

Decided to report this for fs-uae since I don't use WinUAE anymore (I am exclusively on Debian GNU/Linux).
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