YMF795 Datasheet, PDF (3/45 Pages) YAMAHA CORPORATION – APL-2 Automobile sound Player-2

YMF795
■General Description of YMF795
YMF795 is controlled through the serial interface.
Internal configuration the LSI has is shown below.
SDIN
SYNC
SCLK
/IRQ
Serial
interface
Musical score
data
Volume, power management, etc.
Timbre Data
Tempo
START/STOP
Timbre allocation
Timbre
register
FIFO
32word
Sequencer
FM
Synthesizer
D/A +
Volume
AMP
HPOUT
SPOUT
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).
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