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6809: Document direct addressing mode

This commit is contained in:
Karol Stasiak 2020-07-31 01:57:10 +02:00
parent f0b083abea
commit 8ec82ef520
2 changed files with 7 additions and 0 deletions

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@ -42,6 +42,11 @@ but you need to be careful with using absolute vs immediate addressing:
}
return result
}
To use the direct addressing mode, prepend the argument with `<`:
CLR <$6f // clears the byte $6f in the direct page
CLR $6f // clears the byte $006f (absolute address!)
Any assembly opcode can be prefixed with `?`, which allows the optimizer change it or elide it if needed.
Opcodes without that prefix will be always compiled as written.

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@ -30,5 +30,7 @@ Colons are required in label declarations.
* 6809: `0,X` is assembled the same as `,X`.
* 6502: To enforce direct-page addressing, prepend the argument with `<`: `<arg`.