ymf795 Yamatake Corporation, ymf795 Datasheet - Page 18

• Manufacturer Part Number: ymf795
• Description: Apl-2 Automobile Sound Player-2
• Manufacturer: Yamatake Corporation

$33h Clock selection
Default: 0000h
$34h Interrupt control
Default: 0000h
Index
$33h
Index
$34h
The musical score data is taken into the FIFO which has a capacity for 32 data. As the sounds are reproduced, the data in
FIFO are processed and deleted. And when the amount of data remaining in FIFO becomes less than the setting value of
IRQ point, an interrupt signal is generated. At this point, set “0” to IRQE and then write the subsequent musical score
data into FIFO.
Be sure to write data in excess of the IRQ point. After writing the data, reset IRQE to “1” and wait another interrupt
signal.
IRQ point can be set in 32 ways from 0 (empty) to 31 (1 data vacancy).
IRQE is the interrupt enable bit. “1” indicates Enable.
This register is used to set the clock frequency inputted through CLK_I pin when making the clock setting in the
preset mode.
A clock with any frequency can be input during the reset period.
(For details of the clock setting, see “On clock frequency setting” (page 24)).
(*)When clock is set in the programmable mode, set CLKSEL[2:0] to “0h”.
b15
b15
0
0
CKSEL [2:0]
b14
b14
0
0
0h(*)
1h
2h
3h
4h
5h
6h
7h
b13
b13
0
0
b12
b12
0
0
Clock frequency (MHz)
b11
b11
0
0
19.200
19.680
19.800
14.400
27.821
12.600
b10
b10
2.688
8.400
0
0
b9
b9
0
0
-18-
b8
b8
0
0
b7
b7
0
0
b6
b6
0
0
IRQE
b5
b5
0
b4
b4
0
b3
b3
YMF795
0
IRQ point
b2
b2
CLKSEL
b1
b1
b0
b0