ADC $hhll, X
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| Mnemonic: | ADC $hhll, X | ||||||
| 2. Schreibweise: | {{{2. Schreibweise}}} | ||||||
| Opcode: | $7D | ||||||
| Operator(en): | $ll $hh | ||||||
| Byte count: | 3 | ||||||
| Command type: | Arithmetic- and logic command | ||||||
| Address mode: | absolute X indexed | ||||||
| register flags: | |||||||
| Carry Flag | |||||||
| Negative Flag | |||||||
| Overflow Flag | |||||||
| Zero Flag | |||||||
| Cycles: | 4 | ||||||
| 1 cycle when crossing page boundary | |||||||
The assembler command ADC $hhll, X adds the content of memory location ($hhll + X) to the accumulator.
If the carry flag is set the result is incremented by one.
Therefore the carry flag should be cleared with CLC before an addition; unless the behaviour is intended.
The result is stored in the accumulator.
If the result is bigger than 255 ($ff) the carry flag is set as overflow bit.
Function flow
Explanation of the mnemonic shortcut
| ADC | ADd with Carry |
| Add accumulator with operator and carry flag |
