YMF795

-3-

■General Description of YMF795

YMF795 is controlled through the serial interface.

Internal configuration the LSI has is shown below.

Data inputted to the serial interface is converted into the parallel data and transferred to each function block according

to its index address.

The musical score data is stored in the 32-word FIFO first and then transferred to the sequencer which interprets data

to control sound generation of the FM synthesizer.

The timbre register is where up to 8 timbre data can be stored.

And, as the sequencer controlling register, registers for start/stop and tempo are provided.

In order to have sound generate, the following controls must be performed to this LSI.

1) Initial status setting (cancellation of power-down, clock selection, etc).

2) Timbre data setting.

3) Writing of the musical score data into FIFO before starting the sequence.

4) To write the next musical score data write before the FIFO becomes empty, and to receive the interrupt signal

from FIFO during reproduction.

(For the details, refer to “Settings and procedure required for a piece generation” (P.24).

Serial

interface

FIFO

32word

/IRQ

Sequencer

FM

Synthesizer

D/A +

Volume

AMP

Timbre

register

Musical score

data

Tempo

START/STOP

Timbre allocation

Timbre Data

Volume, power management, etc.

SDIN

SYNC

SCLK

SPOUT

HPOUT