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Elite on the BBC Micro

Loader: do_BYTEV [Elite-A, Loader]

Name: do_BYTEV [Show more] Type: Subroutine Category: Loader Summary: The custom handler for OSBYTE calls in the BBC Master version
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * set_vectors calls do_BYTEV
\ --- Mod: Whole section added for Elite-A: -----------> .do_BYTEV CMP #143 \ If this is not OSBYTE 143, the paged ROM service call, BNE old_BYTEV \ then jump to old_BYTEV to pass the call onto the \ default handler CPX #&F \ If the value of X is not &F ("vectors changed"), jump BNE old_BYTEV \ to old_BYTEV to pass the call onto the default \ handler JSR old_BYTEV \ This is OSBYTE 143 with X = &F (the "vectors changed" \ service call), so first of all call old_BYTEV so the \ service call can be processed by the default handler \ And then fall through into set_vectors to set the \ FILEV, FSCV and BYTEV vectors to point to our custom \ handlers \ --- End of added section ---------------------------->