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6502

6502 beginner question: where is the carry flag?


I'm following this tutorial: https://skilldrick.github.io/easy6502/

and in the Registers and flags section there is a part that says "If you were looking carefully enough, you’ll have noticed that the carry flag was set to 1 after this operation. So that’s how you know."

The trouble is, I can't identify where the carry flag is shown.

Right before the Instructions it states: "The last section shows the processor flags. Each flag is one bit, so all seven flags live in a single byte."

Here's what I'm seeing:


Solution

  • According to this site, the last line in your screenshot which is 10110001 is the flags sections and the rightmost bit is the Carry Flag

    7  bit  0
    ---- ----
    NVss DIZC
    |||| ||||
    |||| |||+- Carry
    |||| ||+-- Zero
    |||| |+--- Interrupt Disable
    |||| +---- Decimal
    ||++------ No CPU effect, see: the B flag
    |+-------- Overflow
    +--------- Negative