Yamaha YMF744B (DS-1S) specifications DMA Emulation Protocol, Pc/Pci

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YMF744B

3. DMA Emulation Protocol

The former synthesizer LSI for the ISA bus such as the Sound Blaster used the DMA controller (8237: ISA DMAC) on the system to transfer the sound data from/to the host.

For DS-1S, however, ISA DMAC must be used to transfer the sound data to the Sound Blaster Pro Block of the Legacy Audio Block.

Because signals to connect to the ISA DMAC are generally not available on the PCI bus, there are two ways proposed from the industry to emulate the ISA DMAC on the PCI bus. One is PC/PCI and the other is D- DMA.

DS-1S supports both protocols for transferring SB Pro sound data on the PCI bus.

3-1. PC/PCI

DS-1S provides two signals, PCREQ# and PCGNT# to realize the PC/PCI. The format of the signals is shown below. DS-1S asserts PCREQ# and sets PCREQ# to “HIGH” using the PCICLK corresponding to the DMA channel it is going to use.

In addition, DS-1S determines whether the next PCI I/O cycle is its own from the channel information that is encoded in PCGNT#.

0ns

100ns

200ns

300ns

400ns

PCICLK
REQ#	start CH0 CH1 CH2 CH3 CH4 CH5 CH6 CH7
	start CH0 CH1 CH2 CH3 CH4 CH5 CH6 CH7
GNT#	start bit0 bit1 bit2
	start bit0 bit1 bit2

PCGNT# is encoded as follows.

GNT# Encoding

bit2	bit1	bit0	GNT# Bits
0	0	0	DMA Channel 0
0	0	1	DMA Channel 1
0	1	0	DMA Channel 2
0	1	1	DMA Channel 3
1	0	0	Reserved
1	0	1	DMA Channel 5
1	1	0	DMA Channel 6
1	1	1	DMA Channel 7

DS-1S supports only 8-bit DMA channels (DMA Channel 0-3). It also only supports Single DMA transfer.

February 3, 1999

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Contents Overview FeaturesPreliminary Logos GM system levelSensaura February 3PIN Configuration YMF744B-V 0.5mm pin pitchYMF744B-R 0.4mm pin pitch AC’97 Interface 8-pin PIN DescriptionPCI Bus Interface 54-pin Miscellaneous 11-pin External Audio Interface 5-pinLegacy Device Interface 15-pin Power Supply 22-pin Reserve Pin 13-pinBlock Diagram PC/PCI IRQPCI Bus Command Target Device ModeMaster Device Mode Function OverviewPCI Configuration Register 5C-5Fh02-03h Device ID 04-05h Command00-01h Vendor ID 06-07h Status 08h Revision ID 09h Programming Interface0Ah Sub-class Code 0Bh Base Class Code10-13h PCI Audio Memory Base Address 0Dh Latency Timer0Eh Header Type 18-1Bh Legacy Audio I/O Base Address Dummy for Joystick B0................IO Read Only2C-2Dh Subsystem Vendor ID 2E-2Fh Subsystem IDB150 ........Subsystem Vendor ID B150 ........Subsystem ID34h Capability Register Pointer 3Ch Interrupt Line3Dh Interrupt Pin 3Eh Minimum Grant3Fh Maximum Latency 40-41h Legacy Audio ControlB4................MIEN MPU401 IRQ Enable B5................I/O I/O Address Aliasing ControlB76 ..........SDMA Sound Blaster DMA-8 Channel Select B108 ........SBIRQ Sound Blaster IRQ Channel SelectB14..............SIEN Serialized IRQ enable B1211 ......SMOD SB DMA mode42-43h Extended Legacy Audio Control B8................MAIM MPU401 Acknowledge Interrupt Mask44-45h Subsystem Vendor ID Write Register 46-47h Subsystem ID Write RegisterRead / Write Default 0001h Access Bus Width 8, 16, 32-bit Crst AC’97 Software Reset Signal ControlWrst AC’97 Warm Reset 48-49h DS-1S Control4A-4Bh DS-1S Power Control 4C-4Dh D-DMA Slave Configuration 4E-4Fh DS-1S Power Control B12 Psacl Power Save AC-LinkPsio Power Save I/O Pad 50h Capability ID B70 ..........Capability ID Capability Identifier51h Next Item Pointer 52-53h Power Management Capabilities54-55h Power Management Control / Status 58-59h Acpi Mode 5A-5Bh DS-1S Secondary AC’97 Power Control60-61h FM Synthesizer Base Address 62-63h Sound Blaster Base Address64-65h MPU401 Base Address 66-67h Joystick Base AddressB151 ........MPU401 Base Address B150 ........Joystick Base AddressISA Compatible Device DS-1S FM Synthesizer Status Register RO FM Synthesizer BlockStatus Register FM Synthesizer Data Register Array 1 R/W FM Synthesizer Data RegisterFM Synthesizer Data Register Array 0 R/W Sound Blaster Pro Block DSP Command CMDSound Blaster Pro Mixer SB Mixer DSPVolume for Midi SB Mixer AC’97B0................SBPDR Sound Blaster Power Down Request SE Scan EnableSM Scan Mode Sbpda Sound Blaster Power Down Acknowledgement F1h Scan In/ Out Data F2h Current FM Synthesizer Index F3h Current FM Synthesizer Array F4h FM Synthesizer / MPU401 StatusFfemp FM Synthesizer Empty F8h Interrupt Flag Register MPU401Joystick SB IRQ StatusDMA Emulation Protocol PC/PCIDMA Interrupt Routing Serialized IRQHardware Volume Control Digital Audio Interface SpdifZoomed Video Port Sclk Data LrckChannel Speaker System Multiple AC’97 & Multi-ChannelAC’97 Digital Docking Recommended Operating Conditions Electrical CharacteristicsAbsolute Maximum Ratings DC Characteristics Master Clock AC CharacteristicsReset PCI Interface PCI Clock timingAC’97 Master Clock Master Clock timing for AC’97AC-link AC-link timingZoomed Video Port Zoomed Video Port timingExternal Dimensions Unit mm February 3YMF744B-R Yamaha Corporation