MOVEF
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Jump to navigationJump to searchNote: This article describes the MOVAF routine for transferring floating point values in BASIC-ROM.
| Name: | MOVAF | ||||||
| Description: | Round floating point register FAC and copy to floating point register ARG. | ||||||
| Entry point: | $BBFC / 48124 | ||||||
| Passed arguments: | |||||||
| Return values: | |||||||
| Accumulator: | Exponent of FAC and ARG | ||||||
| X-Register: | 0 | ||||||
| Y register: | unchanged | ||||||
| zero flag: | set | ||||||
| Negative flag: | deleted | ||||||
MOVAF[1] — sometimes also ARGFAC[2] or FAC2/1[3] — copies the contents of the floating point register ARG and into the floating point register FAC and sets its rounding byte to 0.
Runtime behavior[edit | edit source]
The running time of MOVAF is always 87 system cycles, regardless of the content of ARG.
Weblinks[edit | edit source]
- Disassembly of MOVAF/$BBFC on All About Your 64
- CodeBase 64: Floating Point Math
- C64 BASIC & KERNAL ROM Disassembly by Michael Steil
- C64OS: Floating Point Math from BASIC
