Difference between revisions of "SCUMM/V5 opcodes"
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Jestar jokin (talk | contribs) m (→override: clarify) |
Jestar jokin (talk | contribs) m (aux opcodes are always 01) |
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|opcode||The instruction's opcode, with the appropriate bits set according to the parameters. | |opcode||The instruction's opcode, with the appropriate bits set according to the parameters. | ||
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|aux||An aux opcode that stores parameter bits and no other information. | |aux||An aux opcode that stores parameter bits and no other information. (the base aux opcode seems to always be $01) | ||
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|sub-opcode||An aux opcode that indicates a specific function to perform (e.g. the "wait" instruction has sub-opcodes to "wait for message", "wait for actor" etc), as well as storing parameter bits if necessary. | |sub-opcode||An aux opcode that indicates a specific function to perform (e.g. the "wait" instruction has sub-opcodes to "wait for message", "wait for actor" etc), as well as storing parameter bits if necessary. | ||
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|value[p16]||A 16-bit parameter. This is always encoded as a word LE, and may be a pointer or constant. | |value[p16]||A 16-bit parameter. This is always encoded as a word LE, and may be a pointer or constant. | ||
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|value[v16]||A variable number of word LE parameters. These are encoded as a sequence of aux[8] param[p16]; param; aux contains the parameter bit to describe param. A byte of $FF terminates the sequence. (actually always shown as "value[v16]...") | |value[v16]||A variable number of word LE parameters. These are encoded as a sequence of aux[8] param[p16]; param; aux contains the parameter bit to describe param (and is always $01, ignoring the parameter bits). A byte of $FF terminates the sequence. (actually always shown as "value[v16]...") | ||
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|value[o]||The offset word for parameter value. This is only encoded if needed, but always at the position indicated. If not specified, the offset word occurs immediately after the parameter. | |value[o]||The offset word for parameter value. This is only encoded if needed, but always at the position indicated. If not specified, the offset word occurs immediately after the parameter. | ||