The Oxygen Express™-series HD CM8888 is a high- quality PCI Express multi-channel audio processor with an Intel HD Audio specification-compatible audio chip. It is also a controller that can link HDA codecs or bridge high-quality I2S codecs. The CM8888 can be built into home audio electronics or personal computers to provide high-fidelity sound, providing a professional audio processing center.

It supports up to 14 outgoing channels and 12 ingoing channels. The 14 outgoing channels are composed of 4 playback DMA’s, including a multi-channel DMA (32 bits, 8 channels, 192k), a S/PDIF & HDMI DMA (each 32 bits, 2 channels, 192k), and a RTC (real-time communication) DMA (32 bits, 2 channels, 192k) channels. The 12 ingoing channels are spread out in 3 recording DMAs (up to 32 bits, 192k).

 

Bus

• Compatible with PCI Express 1.1 interface, with bus mastering and burst modes

Architecture

• Embedded 8051-based MCU transcodes HD Audio commands to link various external I2S codecs (external 4 or 8KB serial EEPROM is required)
• Embedded ROM code for MCU transcoding of HD Audio commands for embedded DACs and ADCs
• Built-in HD Audio and I2S controllers offer flexibility in choosing external codecs for different product applications
• Digital mixer to mix all input data to output streams

Audio I/O
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• Intel HD Audio Link supports 1 external HDA codec
• Six pairs of I2S serial audio output interfaces (12-ch out)
• Six pairs of I2S serial audio input interfaces (12-ch in)
• Integrated 192K/176.4K/96K/88.2K/48K/44.1K, and 16/24/32-bit S/PDIF transmitter with a 2-source selector/mux (from playback DMA digital mixing, S/PDIF input), including WMA-Pro output support
• Integrated 192K/176.4K/96K/88.2K/48K/44.1K, and 16/24/32-bit S/PDIF receiver with 2-input internal selector/switch for media center/AV receiver features
• Built-in MPU-401 MIDI UART I/O port for pro audio applications
• All input data can be mixed to output streams for low-latency record monitoring/mixing output

Control Interfaces

• SPI control interfaces with up to 8 external audio devices (5 output devices and 3 input devices)
• I2C Interface supports both master and slave modes (master for external audio devices and slave for additional MCU applications such as remote controls)
• Interrupt pin for external MCU read transaction
• Serial EEPROM programming interface for customizing sub-vendor and sub-device IDs (and vendor/device IDs as well), storing HDA power-on pin configuration data (replacing the MB BIOS function) and 8051 ROM codes (HDA command transcoder
• Maximum 8 jack-detection pins (5 for output jacks and 3 for input jacks)
• Maximum 16 GPIO pins for external devices control and other purposes
• LED indicator control pin functions while protected content is playing

General

• 24.576MHz crystal input required with embedded PLL for adaptive clock rate
• Single 3.3V power supply
• 3.3 V digital I/O pads with 5V tolerance
• Fully compatible with all mainstream southbridges (Intel, nVIDIA, VIA, SiS)
• LQFP-128 package
• Default target codecs: CM9882A for HDA; CS5381 (ADC)+PCM1795(DAC) for I2S
• Support Xear™ technology by Cmedia vendor driver