Sym-1: What is the "f" register?

Question

Running SUPERMON on a Synertek SYM-1, the R (REG) command cycles through a number of registers. Most are self explanatory:

But what is f?

.r
P 8B4A,>
S   FF,>
F   00,>
A   00,>
X   00,>
Y   00,
.

Justme · Accepted Answer · 2021-02-01 21:33:53Z

19

The only thing missing from your list of processor state is the flags register.

answered Feb 1, 2021 at 21:33

Justme

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Thank you for helping my feeble brain. In my head I think "status register", not "flags register".
– larsks
Feb 1, 2021 at 21:37
2

Brilliant Answer :))
– Raffzahn
Feb 1, 2021 at 22:00
4

In 6502 assembly, the status flags register is given the initial P (PHP and PLP). Both P and S are already used to denote the Program Counter and the Stack Pointer in SUPERMON, so F is the next logical choice and is indeed available.
– Chromatix
Feb 1, 2021 at 23:36

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