Sound Generator Control Registers - NEC mPD780973 Series Preliminary User's Manual

17.3 Sound Generator Control Registers

The following three types of registers are used to control the sound generator.
• Sound generator control register (SGCR)
• Sound generator buzzer control register (SGBR)
• Sound generator amplitude register (SGAM)
(1) Sound generator control register (SGCR)
SGCR is a register which sets up the following four types.
• Controls sound generator output
• Selects output of sound generator
• Selects sound generator input frequency f
• Selects 5-bit counter input frequency f
SGCR is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears SGCR to 00H.
Figure 17-3 shows the SGCR format.
CHAPTER 17 SOUND GENERATOR
SG1
SG2
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