FEDL 2213-01

1Semiconductor

ML2213

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7.2 Musical Note Data

Musical note data consists of 2 bytes and is stored in the Mask ROM’s User’s Data area, where a user can define

scale, note and the end-bit for a music phrase. Table 7.2 shows the coding format for musical note data.

Table 7.2 Coding Format for Musical Note Data

NSB

7SB

6SB

5SB

4SB

3SB

2SB

LSB

The First Byte

END-Bit

0

L5

L4

L3

L2

L1

L0

Musical Note Code

The Second Byte

N7

N6

N5

N4

N3

N2

N1

N0

Musical Scale Code

(1) Musical Scale Code

Musical scale code is defined at the second byte. The following equation shows output frequency from the Music

Generator circuit at 4.096 MHz external clock.

kHz (“N” is integer between 4 to 127)

Co-relationship between “N” and musical scale can be calculated as follows:

N = 2

When all values for N7 to N2 are set to “0”, no music is reproduced during the period specified by the note code.

At this instance, the values of N1 and N0 have no significance (Don’t care).

Table 7.3 shows major musical scales (keys) and their corresponding scale codes.

32

(N + 2)