Specifications

I-88 EPSON S1C62N82 TECHNICAL HARDWARE

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)

Writing on the mask register should always be performed in the

"DI (interrupt prohibited)" state. Otherwise, misoperation may

result.

(m)Melody output control circuit

Melody output is masked by setting MELD to 1 and is

unmasked by setting it to 0.

Since this function operates independently from the

melody generator, control of melody generator other than

this control circuit is required in order to generate

melody.

Valid

Approx. 7.8 ms

PlayingPlaying

End-of-melody

signal

Melody interrupt

signal

Interrupt factor

flag

Melody signal

generator

block

MELD

Address "0F4H"

Data bus

Melody signal

Fig. 4.11.12

Melody output control circuit

Fig. 4.11.11

Interrupt generation timing

Note

(n) Melody output terminal (MO and R12)

These are terminals which generate melody during

performance. The performance type (piezo buzzer direct

driving and envelope addition) of the melody is deter-

mined by mask option. The output configuration and

output waveform of these terminals are shown in Figure

4.11.13. The configuration varies with the mask option

selection of R12.

Moreover, whether each option will by set as normal

HIGH level output or normal LOW level output may be

selected through mask option.