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From: Crown (all posts)
Date: 1998-06-08
Subject: Minus4 BRK & B flag
Hi there,

Mike:
The B flag of the status regs is a fantom flag, it is not existent, it's always set, when a normal IRQ happens (raster, timer IRQ) it pushes the flags to the stack and-ed with 0xef.
Also in the BRK instruction you should set the I flag,
after the flags has been pushed to the stack, and I guess the line debug=1
is not needed, as If I remember right BRK was used in some games.

Merceneray works after fixing the V bit calculations in ADC and SBC !!! There might be still some bugs, as this didn't solved the problems with One-on-One :-(

Tibor Biczo / Crown of GOTU

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