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BBC Micro Elite

Sound: FNE (6502SP version)

Name: FNE [View in context] Type: Macro Category: Sound Summary: Macro definition for defining a sound envelope
The following macro is used to define the four sound envelopes used in the game. It uses OSWORD 8 to create an envelope using the 14 parameters in the the I%-th block of 14 bytes at location E%. This OSWORD call is the same as BBC BASIC's ENVELOPE command. See variable E% for more details of the envelopes themselves.
MACRO FNE I% LDX #LO(E%+I%*14) \ Set (Y X) to point to the I%-th set of envelope data LDY #HI(E%+I%*14) \ in E% LDA #8 \ Call OSWORD with A = 8 to set up sound envelope I% JSR OSWORD ENDMACRO