work on best low cost mp3 player for rockbox

[wodz]

No BGA seems strange for me. Mass production using BGA chips is actually cheaper, PCB can be of higher density etc. etc. BGA may be hard for hobbiests but this is really industrial starndard for something like 15 years now.
ATJ213x is capable enough to run rockbox. I am working on the port for this platform but my spare time is very limited nowadays.

[hunterleo]

BGA is not a big problem. However, it increased the defect rate of the device, if my manufacturer wasn't wrong about it. Ingenic 4760 costs about $50 for just the chip. It is too expensive for a low cost player.

ATJ213x's biggest problem is the power consumption which is about 32mA per hour for music playback. ATJ2127 is about 12mA per hour.

[wodz]

When I did research for my hobby project, imx233 from Freescale was the most cost effective solution (pamaury mentioned it already) BUT I considered only chips available is single pieces in Europe.

I am not contesting provided power consumption numbers (as I don't have proper documentatin) BUT SoC consumes usually only tiny fraction of whole system power draw. At what conditions provided consumption was measured?

[hunterleo]

When I did research for my hobby project, imx233 from Freescale was the most cost effective solution (pamaury mentioned it already) BUT I considered only chips available is single pieces in Europe.

I am not contesting provided power consumption numbers (as I don't have proper documentatin) BUT SoC consumes usually only tiny fraction of whole system power draw. At what conditions provided consumption was measured?

The test result is Chinese. I tried to translate it into English.

ATJ2137:
Original OS , LCD 1.8 TFT, battery 3.8V, volume level 24 music playback ,screen on, 52mA
Original OS , LCD 1.8 TFT, battery 3.8V, volume level 24 music playback ,screen off, 32mA

ATJ2127
Original OS , LCD 1.8 TFT, battery 3.8V, volume level 24 music playback ,screen on, 22mA
Original OS , LCD 1.8 TFT, battery 3.8V, volume level 24 music playback ,screen off, 12mA

 I will look into imx233 from Freescale which I wasn't familiar with. Thanks a lot.

[ZincAlloy]

Low power consumption sure is the strong point of the ATJ2127. Is that only possible because it has rather limited possibilities?

[wodz]

I can't say definitely rockbox will do much better but eCOS based original firmware for atj213x is, lets put it mildly, suboptimal. At least the versions I disassembled so far.

[hunterleo]

Low power consumption sure is the strong point of the ATJ2127. Is that only possible because it has rather limited possibilities?

It's phone era now. Many chip makers don't pay much attention at mp3 player now. Not much options out there.

[hunterleo]

I can't say definitely rockbox will do much better but eCOS based original firmware for atj213x is, lets put it mildly, suboptimal. At least the versions I disassembled so far.

So, we can make power consumption of ATJ213X with rockbox lower? What device are you working on a new port for ATJ213X. Can I help you in any way?

[pamaury]

I would be extremely careful with manufacturer figures. For example the Fuze+ with Freescale OS lasts 25h on a 550mAh battery but Rockbox lasts around 45h. And most of the savings don't come from the CPU, since with proper frequency management you can decrease it a lot,  but rather properly shutting down or suspending LCD, touchpad, mmc/sd.

[wodz]

I am working on Iriver e100/150/200/300 series (e150 is my playground). If you have documentation for atj213x (or more precisely the one I don't have) that would be helpful.

[saratoga]

ATJ213XX is pretty old, so it may not be as efficient as newer parts.  Still, well optimized most chips do roughly 1.5 to 2x what the vendor claims once properly optimized.

The new atj cores without dram do well by having such simple hardware, but not that well. The old as3525v2 uses nearly the same current once voltage scaling is enabled, and it has real dram and no DSP, just arm9e. I think the DSP is more about cost savings than anything.

[hunterleo]

I would be extremely careful with manufacturer figures. For example the Fuze+ with Freescale OS lasts 25h on a 550mAh battery but Rockbox lasts around 45h. And most of the savings don't come from the CPU, since with proper frequency management you can decrease it a lot,  but rather properly shutting down or suspending LCD, touchpad, mmc/sd.

Great! Thanks for the advice.  I will list all the chips available, and let's figure them out which one is best for rockbox.

[hunterleo]

I am working on Iriver e100/150/200/300 series (e150 is my playground). If you have documentation for atj213x (or more precisely the one I don't have) that would be helpful.

Could you list the documentation precisely you don't have? I checked with the manufacturer, they have several versions (new and old)of packages of documentation for the chip is quite old.

[wodz]

I have lots of various documents BUT the crucial one I have are:
Actions ATJ2135N Product Datasheet version 1.0 dated May 2008
Actions ATJ2135 Product Programming Guide version 1.1 dated January 2007

1) I'd love to have linux sources (which I know exist for atj2137n) and some document describing various members of this family (what is the difference between 2135 and 2137 etc.).
2)USB controller is not documented at all in datasheet. I have some idea how it works (I ported hwstub and it works pretty well) based on reverse engineering but thats it.
3)Flash controller documentation is vague and incomplete in datasheet.
4)DSP core is not documented. I know it is instruction compatible with ADSP-21xx but I suspect it has 24bit data path and have some custom registers.
5)Documentation for eCOS SDK would be nice - what are components:
 - what is BREC, MBREC how they are stored on flash
 - how exactly boot process is done
 - what is actually run on DSP
6)I have no idea what FTL is used.

Any help in this topics is appreciated.

[hunterleo]

OK. wodz. I will search them.