Specifications

I-102 EPSON S1C62N82 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

The relationship between MELC register value and play-

ing output is shown in Figure 4.11.18.

(c)Retrigger mode

This playing mode is for modifying or stopping the melody

forcedly in the middle of playing. Its operating procedure

is as follows:

(1)In the middle of a melody playing, write the melody

ROM address of the next melody to be played on the

address register (MAD0–MAD6).

(2)Change the MELC register setting from "0" to "1". At

this point, the played melody will be forcedly changed.

(3)After this operation, the 3 types of playing mode may

be selected freely again.

To stop a melody in the middle of its playing is also

implemented by employing this mode. The operation is

as follows:

(1)In the middle of a melody playing, set the melody ROM

address written with silent notes on the address

(2)Change the MELC register setting from "0" to "1" and

then to "0" again.

Fig. 4.11.18

Level hold mode

Approx. 125 ms

Generation of

melody interrupt

Melody

Playing

"MELC"

Melody

....

Melody

n-1

Melody