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Re: Break Flag Is A Mystery



On Dec 26, 4:04 pm, "Bryan Parkoff" <nos...@nospam.com> wrote:
>     Only true documenation of NMOS 6502 MPU can be shown 1976 Synertek
> Programming Manual.  It is not necessary to prove 4th flag to be reserved,
> but you did obversation to know what Break flag is doing.

Yes, this reasonably well known to experienced 6502 programmers. Your
observations are also confirmed in:

Jim Sather's "Understanding the Apple II", page 4-18
Jim Sather's "Understanding the Apple IIe", page 4-18
David Eyes/Ron Lichty "Programming the 65816", page 30