YMF744B

14-17h: Legacy Audio I/O Base Address (Dummy for SB, FM, MPU, D-DMA)

Read / Write

Default: 00000001h

Access Bus Width: 8, 16, 32-bit

 

b15

b14

 

b13

b12

b11

 

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IOBASE0

 

 

 

 

-

-

-

-

-

I/O

 

b31

b30

 

b29

b28

b27

 

b26

b25

b24

b23

b22

b21

b20

b19

b18

b17

b16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-

-

 

-

-

-

 

-

-

-

-

-

-

-

-

-

-

-

b0................IO

 

(Read Only)

 

 

 

 

 

 

 

 

 

 

 

This bit indicates that the base address is assigned to I/O. This bit is hardwired to “1”.

b[15:6]

IOBASE0

This register is used so that the OS may secure I/O resources for Sound Blaster Pro, FM Synthesizer, MPU401 and D-DMA controller. Because this register is a dummy one, each for the I/O addresses of the above blocks is assigned with the I/O addresses set to 4C-4Dh and 60-65h respectively by the software driver.

18-1Bh: Legacy Audio I/O Base Address (Dummy for Joystick)

Read / Write

Default: 00000001h

Access Bus Width: 8, 16, 32-bit

 

b15

B14

 

b13

b12

b11

 

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IOBASE1

 

 

 

 

 

 

-

I/O

 

b31

B30

 

b29

b28

b27

 

b26

b25

b24

b23

b22

b21

b20

b19

b18

b17

b16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-

-

 

-

-

-

 

-

-

-

-

-

-

-

-

-

-

-

b0................IO

 

(Read Only)

 

 

 

 

 

 

 

 

 

 

 

This bit indicates that the base address is assigned to I/O. This bit is hardwired to “1”.

b[15:2]

IOBASE1

This register is used so that the OS may secure I/O resource for the joystick port. Because this register is a dummy one, the joystick I/O address is assigned with the I/O address set to 66-67h by the software driver.

February 3, 1999

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Yamaha YMF744B (DS-1S) 18-1Bh Legacy Audio I/O Base Address Dummy for Joystick, B0................IO Read Only

YMF744B (DS-1S) specifications

The Yamaha YMF744B, also known as the DS-1S, is a popular audio chip that emerged in the late 1990s, particularly known for its use in sound cards for PCs. This sound processor exemplifies Yamaha's commitment to delivering high-quality audio through innovative technology and user-friendly features.

One of the standout features of the YMF744B is its ability to support advanced sound synthesis methods, including wave table synthesis and sample playback. These technologies provide users with a rich audio experience, enabling high-fidelity sounds reminiscent of live instruments. The chip is also notable for its ability to emulate MIDI instruments, allowing musicians to create synthesized music that captures the nuances of traditional sounds.

The YMF744B integrates a 16-bit DAC (Digital-to-Analog Converter), which facilitates high-quality audio playback with a sampling rate of up to 48 kHz. This capability ensures that sound reproduction remains clear and devoid of distortion, appealing to both casual users and audio professionals alike. Additionally, the chip supports multiple audio channels, making it ideal for gaming and multimedia applications where spatial audio is crucial.

Another significant feature of the YMF744B is its support for various audio formats, including PCM (Pulse Code Modulation), ADPCM (Adaptive Differential Pulse Code Modulation), and even MIDI. The versatility in format support allows users to interact with a broad spectrum of audio applications, from game design to music production.

The chip also comes with integrated Sound Blaster Pro compatibility, which significantly enhances its usability with a vast array of software and games designed during the 1990s and early 2000s. This compatibility is crucial for retro gaming enthusiasts who seek an authentic audio experience with classics from the past.

Moreover, the YMF744B champions power efficiency, making it an attractive choice for mobile computing platforms. Its low power consumption means that it can be effectively used in laptops without significantly draining battery life, allowing users to enjoy high-quality sound on the go.

In summary, the Yamaha YMF744B (DS-1S) stands out due to its advanced audio synthesis capabilities, high-quality playback features, and compatibility with multiple formats. These attributes make it a favored choice in the audio processing domain, continuing to impact computer audio technology long after its initial release.