Because the Apple II lacks interrupts, game developers had to synchronize their main loops with the vertical blank of the screen to achieve smooth animation. Sound presented a unique challenge on the Apple II, as there were no interrupts to assist with audio playback. The introduction of sound add-on cards like the Mockingboard addressed this issue by providing the necessary interrupts. The process of installing the Mockingboard 4c+, which emulates the original Mockingboard, involves replacing the CPU and wiring the volume control pots. Overall, the Mockingboard enhanced the Apple II’s sound capabilities significantly, making it a valuable addition for gaming and audio playback.
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