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software:upi_conventions [2016/06/14 10:20] ex_writer [User-Defined Subroutines] |
software:upi_conventions [2016/06/14 10:25] ex_writer [User-Defined Subroutines] |
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| - | <code>The UPI has been extended to support user-supplied routines. If the call index provided is negative [or from $ff through $80] then the users dispatch table pointer (USERTB) is used [also UMARGT]. Note that the sign bit isn't zapped before being used as an index, this means that the users dispatch table pointer should point 128 bytes before the first entry.</code> | + | <code>The UPI has been extended to support user-supplied routines. |
| + | If the call index provided is negative [or from $ff through $80] | ||
| + | then the users dispatch table pointer (USERTB) is used [also UMARGT]. | ||
| + | Note that the sign bit isn't zapped before being used as an index, | ||
| + | this means that the users dispatch table pointer should point | ||
| + | 128 bytes before the first entry.</code> | ||
| Also: | Also: | ||
