Conexant CX2388x: Difference between revisions

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Big brother to the [[BT878]] produced by [[Conexant Systems, Inc.]]. Has specialised DVB support in a new PCI function, instead of using the digital audio input for it. (Yay!). In fact it has stacks of functions, like 6 or something, but fortunately they all share the same (huge 16MB!) memory mapping. Has the same (identical?) RISC programs as the BT878 and the same kind of [[I2c_Protocol|i2c bus control]] controller.
Big brother to the [[BT878]] produced by [[Conexant Systems, Inc.]]. Has specialised DVB support in a new PCI function, instead of using the digital audio input for it. (Yay!). In fact it has stacks of functions, like 6 or something, but fortunately they all share the same (huge 16MB!) memory mapping. Has the same (identical?) RISC programs as the BT878 and the same kind of [[I2c_Protocol|i2c bus control]] controller.


For DVB signal reception handling, the cx2388x doesn't really offer anything over the older BT878 chipset.
Note that according to the [http://www.conexant.com/servlets/DownloadServlet/PBR-200192-001.pdf?docid=193&revid=1 product brief], the maximum video signal that this chip can capture is "up to 768 x 576 (square pixel PAL/SECAM)", that is 576p. No true HD signals (720i, 720p, 1080i) can be captured with cards using this chipset. Some countries, such as Australia, have defined HD to be 576p or above, but 576p is not generally considered HD.

====Analog video inputs====
In terms of its analog to digital signal processing capabilities, the cx2388x brings some improvements over the older [[BT878]] chipset.

Like other A/V decoders, the maximum capture window that these chips support with an analog input signal is "up to 768 x 576 (square pixel PAL/SECAM)".


But really for DVB I don't think it gives you anything that the BT878 doesn't. If however you want to put analogue video on the same card (like [[DViCO]] do) then it seems to have a few improvements in that department.


====Analog audio inputs====
====Analog audio inputs====

Revision as of 01:13, 12 March 2007

Big brother to the BT878 produced by Conexant Systems, Inc.. Has specialised DVB support in a new PCI function, instead of using the digital audio input for it. (Yay!). In fact it has stacks of functions, like 6 or something, but fortunately they all share the same (huge 16MB!) memory mapping. Has the same (identical?) RISC programs as the BT878 and the same kind of i2c bus control controller.

For DVB signal reception handling, the cx2388x doesn't really offer anything over the older BT878 chipset.


Analog video inputs

In terms of its analog to digital signal processing capabilities, the cx2388x brings some improvements over the older BT878 chipset.

Like other A/V decoders, the maximum capture window that these chips support with an analog input signal is "up to 768 x 576 (square pixel PAL/SECAM)".


Analog audio inputs

The cx2388x family of ICs are capable of providing demodulation of all major global broadcast audio standards. In other words, they can directly accept S-IF from a TV tuner pll. These signals will in turn be decoded and are output either to the PC's sound card directly via a patch cable (invokes a DAC step), to a digital audio output interface (eg. SPDIF), or to the host via a DMA channel.

The cx2388x IC's do not process other analog audio sources. They do, however, provide the ability to connect directly, via an i2s input port, to a 3rd party audio ADC.


Also see v4l's cx88 page

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