Commodore 64 - Page 6

. Programming Sprites-Another Look 153
Making Sprites in BASIC-A Short Program. ... . .. . . .. 153
Crunching Your Sprite Programs 156
Positioning Sprites on the Screen 157
Sprite Priorities .. .. ... .. .... .. ... .. ... ... .. ... .. .. 161
Drawing a Sprite 162
Creating a Sprite . . . Step by Step 163
Moving YourSprite on the Screen. . .. . . .. . . .. . ... . . .. 165
VerticalScrolling.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 166
The Dancing Mouse-A Sprite Program Example. . . . . .. 166
EasySpritemakingChart.. . ... . ... . . .. . ... . . ... 176
SpritemakingNotes.. . .. . . .. . ... . . .. . . .. . . .. . ... . .. 177
4. PROGRAMMING SOUND AND MUSIC
ON YOUR COMMODORE 64 183
. Introduction 184
Volume Control 186
Frequencies of Sound Waves. . . .. ... ... .. ... .. ... ... 186
. UsingMultipleVoices... . .. . .... . ... .. ... ... . 187
Controlling Multiple Voices 191
. Changing Waveforms . ... .. ... ... ... .. ... .. ... ... .. .. 192
UnderstandingWaveforms..... .... . . ... .... 194
. The EnvelopeGenerator. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 196
. Filtering 199
. Advanced Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 202
. Synchronization and Ring Modulation 207
5. BASICTOMACHINELANGUAGE 209
. What is Machine Language? ... ... .. ... .... ..... ... ... 210
What Does Machine Code Look Like? ... ... .. ... ... ... 211
Simple Memory Map of the Commodore 64 ............ 212
The Registers Inside the 6510 Microprocessor 213
. How Do You Write Machine Language Programs? 214
64MON 215
. HexadecimalNotation..... ... .... ..... .. .. .... .. 215
Your First Machine Language Instruction 218
Writing Your First Program 220
. Addressing Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 221
Zero Page 221
The Stack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 222
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