详细说明：

EM2888芯片是禾瑞亚公司针对数字电视(DVB-T DMB-TH)出的USB主控芯片,此芯片最大的特点是支持模拟＋数字＋ＦＬＡＳＨ．
EM2888 is a multi-function USB device that supports PC camera, NTSC/PAL Video
Capture, audio in/out, and Digital TV capture functions. The chip has CMOS sensor
or video interface, AC97 or PCM interface, transport stream interface, command
serial bus interface, NAND Flash interface, and general I/O ports.
Many ports and buffers are multi-purpose and must be configured at power up before
entering normal operation.
The device uses an embedded microcontroller 8051 to decode USB requests and
control various I/O's. Microcode is stored off chip and downloaded to on-chip
cache at power up. Video stream, audio stream, and transport stream are
directly transferred, bypassing the microcontroller.
Video input can be YUV 4:2:2 or Bayer RGB format. The video data are processed
according to settings in Vendor Registers. An output format transforms the
processed data to various formats in RGB or YUV form, uncompressed.
Final video data are shipped to the USB host via isochronous pipe.
The video function is compliant to USB Video Class.
The audio interface supports AC97 or PCM protocols for both microphone and
speaker functions. Audio in/out can be in linear PCM-16, A-Law, or u-Law
format. An on-chip converter handles all conversion works necessary. The chip
uses isochronous pipes for audio streaming and is compliant to USB Audio Class.
For pin count consideration, the chip supports serial form MPEG2 transport
stream only, using 4 pins. This transport stream interface supports
AES-128 encryption so the data sent through the USB port cannot be played
directly without being decrypted with the same key by the driver or the
application program. If the video port is not used, it can be configured
as the second transport stream port (without encryption).
In order for the transport stream to fit in
the limited bandwidth of USB Full Speed mode a transport stream PID filter is
built in to cut out unnecessary traffic on USB. For added value, an infrared
protocol decoder is integrated on chip that supports NEC, RC5 and RC6 remote
control protocols.
The chip supports two command serial buses for communication with peripheral
chips such as CMOS sensor, DTV demodulator, DTV tuner, and EEPROM. The chip
also integrates an UART for firmware debugging.
The chip supports up to four 8-bit NAND Flash chips with the error correcting
capability for a mass storage device.