YMF754 Datasheet, PDF (19/60 Pages) YAMAHA CORPORATION – DS-1E

YMF754
b[7:6] ..........SDMA: Sound Blaster DMA-8 Channel Select
These bits select the DMA channel for the Sound Blaster Pro block.
“0”:
DMA ch0
“1”:
DMA ch1
(default)
“2”:
reserved
“3”:
DMA ch3
b[10:8] ........SBIRQ: Sound Blaster IRQ Channel Select
These bits select the interrupt channel for the Sound Blaster Pro block.
“0”:
IRQ5 (default)
“1”:
IRQ7
“2”:
IRQ9
“3”:
IRQ10
“4”:
IRQ11
“5” - “7”: reserved.
b[13:11] ......MPUIRQ: MPU401 IRQ Channel Select
When MIEN is set to “1”, these bits select the interrupt channel for the MPU401 block.
“0”:
IRQ5
“1”:
IRQ7
“2”:
IRQ9 (default)
“3”:
IRQ10
“4”:
IRQ11
“5” - “7”: reserved
Same interrupt channels can be assigned to SBIRQ and MPUIRQ.
b14..............SIEN: Serialized IRQ enable
DS-1E supports 3 types of interrupt protocols: PCI interrupt (INTA#), Legacy interrupt (IRQs) and
Serialized IRQ. The interrupt protocol is selected with IMOD and SIEN as follows.
The interrupt channels for IRQs and Serialized IRQ are determined by SBIRQ and MPUIRQ,. Only one
protocol can be used at once.
SIEN IMOD Interrupt protocol
0
0
Legacy interrupt (IRQs)
(default)
0
1
PCI interrupt (INTA#)
1
0
Serialized IRQ
1
1
reserved
June 28, 1999
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