home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Apple II Magazines (PO)
/
Nibble Volume 11, No. 09 (1990-09)(MindCraft Publishing)(Side A).zip
/
Nibble Volume 11, No. 09 (1990-09)(MindCraft Publishing)(Side A).po
/
USR2.S
< prev
Wrap
Text File
|
1996-12-24
|
982b
|
32 lines
*************************
* USR2 Source Code *
* MindCraft Assembler *
* By Mark R. Craven *
* Copyright (c) 1990 *
* MindCraft Publ. Co. *
* Concord, MA 01742 *
*************************
ORG $300
FP_TO_INT EQU $E10C
INT_TO_FP EQU $E2F2
NUM_STORE EQU $00A1
SPEAKER EQU $C030
TMP_STORE EQU $0008
JSR FP_TO_INT
LDY NUM_STORE
STY TMP_STORE ;Temporarily Store
JSR INT_TO_FP
PITCH LDX #$10 ;Tone Pitch
TOGGLE LDA SPEAKER ;Toggle Speaker
LDA TMP_STORE ;Retrieve Tone Length
PAUSE DEY
BNE PAUSE
DEX
BNE TOGGLE
DEC TMP_STORE ;Decrement Tone Length
BNE PITCH
RTS