3d power of Ben?

Sergey Kvachonok ravenexp at gmail.com
Thu Dec 9 11:11:23 EST 2010

>> On  the other hand these codecs seem to be jz4750+ only, because they
>> make use of some acceleration hardware not present on jz4740 at all...
> The NN use the Jz4720, see de DataSheet (Sec. 1.2.1 CPU core, pag 8):
> http://www.amebasystems.com/downloads/hardware/datasheets/ben-nanonote/Ingenic-SOC-JZ4720/SOC-U1-Jz4720_ds.pdf
> The Jz4720 have Xburst SIMD instruction set to support multimedia
> acceleration.
> Sadly, those instructions are not documented but the mplayer modified by
> Ingenic  works very well (thanks to HW SIMD acceleration).

No, basic MXU set is documented pretty well in both written english
and equivalent C code. Look at Dingoo site for former and libjpeg
sources for later.

The hardware acceleration I was talking about is not SIMD extenstion
set, but graphical hardware in the form of SoC peripheral. jz4740 has
none, but it appears that jz4755+ have at least IDCT and motion
compensation in silicon.

Check the block diagram at


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