FEDL2215-01
Semiconductor
ML2215
1
7. Volume Setting
The volume of the AOUT pin can be adjusted by applying voltage to the VREF pin.
5
4
3
2
1
0
0
1
2
3
4
5
VREF (V)
Figure 7.1 VREF – AOUT Amplitude
Figure 7.1 shows the relationship between the VREF voltage and the AOUT amplitude. Set the VREF voltage in the
range of 1 to 4 V. The relationship is given by the equation:
AOUT (p-p) 5 − VREF (VREF = 1 to 4 V).
When a volume is not adjusted, leave the VREF pin open.
8. Music Generator
The Music Generator circuit initiates music output via the MD pin by activating a user-defined music phrase from
an external controller. The Music Generator outputs music, automatically acquiring musical notes data stored in
the Mask ROM. Acquiring the last note code where the end-bit is set to “1”, results in stopping playback.
A user can define a music phrase by entering the starting address and tempo data in the Phrase Control Table, and
codes for musical notes and the end-bit information in the User’s Data area. These data for a music phrase, based
on the score of music, can be created and entered by using an OKI’s Analyzing Tool according to coding rules and
formats described later in this document.
8.1 Tempo Data
Tempo data for a music phrase can be defined in the Phrase Control Table while preparing ROM data. Tempo
cannot be changed from an external controller.
Tempo data defines a beat and rhythm for a music phrase. Table 8.1 lists tempos (the count of quarter notes per
minute) available for user’s selection.
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OKI [ OKI ELECTRONIC COMPONETS ]
