YMF744B

b[14:13] ......SBVER: SB Version Select

These bits set the version of the SB Pro DSP. The value set in these bits is returned by sending the E1h

DSP command.

 

“0”:

ver 3.01

(default)

“1”:

ver 2.01

 

“2”:

ver 1.05

 

“3”:

reserved

 

b15..............IMOD: Legacy IRQ mode

The legacy interrupt protocol is selected with IMOD and SIEN. Refer to the explanation of SIEN bit.

44-45h: Subsystem Vendor ID Write Register

Read / Write

Default: 1073h

Access Bus Width: 16-bit

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

Subsystem Vendor ID Write

b[15:0] ........Subsystem Vendor ID Write Register

This register sets the Subsystem Vendor ID that is read from 2C-2Dh (Subsystem Vendor ID register). The default value is the YAMAHA Vendor ID, 1073h. IHVs must change this ID to their Vendor ID in the BIOS POST routine.

In case EEPROM connects externally, this register is invalid, and do not reflect to Subsystem Vendor ID.

46-47h: Subsystem ID Write Register

Read / Write

Default: 0010h

Access Bus Width: 16-bit

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

Subsystem ID Write

b[15:0] ........Subsystem ID Write Register

This register sets the Subsystem ID that is read from 2E-2Fh (Subsystem ID register).

The default value is the DS-1S Device ID, 0010h. IHVs must change this ID to their ID in the BIOS POST routine.

In case EEPROM connects externally, this register is invalid, and do not reflect to Subsystem ID.

February 3, 1999

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Yamaha YMF744B (DS-1S) specifications 44-45h Subsystem Vendor ID Write Register, 46-47h Subsystem ID Write Register

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.