Rockbox Player - Project to design and build a Free/Open hardware audio player

[Bagder]

Also, don't be fooled by the fact that they (can) run Linux. These guys don't release the source for their drivers and the manufacturers of the hardwares don't release their docs to us, so a Linux running on them is very little help to actually get Rockbox ported to them...

[casainho]

Also, don't be fooled by the fact that they (can) run Linux. These guys don't release the source for their drivers and the manufacturers of the hardwares don't release their docs to us, so a Linux running on them is very little help to actually get Rockbox ported to them...

Bagder, I think I understand you. In this case, of AVR32 or AT91SAM(ARM), Atmel gives all information about microcontroller internals, a full datasheet. And also made a GCC port for AVR32, and IDE for Linux

...Rockbox as a stand alone firmware will always have the potential to get better battery life and performance than MPlayer on Linux on the same hardware. So, if you're actually buying a portable player for portability and on-battery use, Rockbox will always be an alternative if you actually want efficiency.

I understand, however, I believe that actual and future hardware will be tailored for portability and on-battery use, AND for multimedia! a good example is the S1mp3 players from China, even these ones are getting to MP4, multimedia! Users will expect a RB system with MP4 for sure.

You said AVR32, but they also have an ARM right? - for what I understand, RockBox have good support for ARMs... what would be the good choice? ARM or AVR32? - Atmel have ARM and AVR32 dev board...

Well it looked like the avr32 had everything but the kitchen sink in it, including the required AC97 D/A, LCD hardware interface, flash memory interface, USB interface, and even ethernet!  Their arm offerings would require external hw to do much of this.  The downside is having to work with BGA packages, but that's what the world is going to.

scharkalvin, can you help to do some analysis between "AT91RM3400 Development Kit User Guide"(ARM) and "AT32NGW100"?

What is the price of each and what external hardware would be need for each board?

I can get one AT32NGW100 for 90 euros at Farnell or Digikey, I am wiling to pay for one If I can help trying make RB working on this hardware, thinking that this hardware will have  long life in market.

In the small company that I work, we don't assembly BGA, just TSOP. My chief told my that maybe in 2 years we will change for wire bounding, so, jumping the BGA tecnhology Future looks like for robots and not humans...

[saratoga]

I'm not really sure what the point of buying a dev kit is, unless you're going to put it into a set top box or some other large unit.  You certainly couldn't make a portable device from one.  But if you don't care about that, make sure it has at least 1-2 MB worth of RAM or you won't be doing much with Rockbox.

[Bagder]

Well dev boards are fine for development, but then (when you have something going) you of course have to make your own board and cram it into a tiny box to make an actual player out of all this.

[scharkalvin]

can you help to do some analysis between "AT91RM3400 Development Kit User Guide"(ARM) and "AT32NGW100

The at32ngw100 is a lower cost (but full featured) development board compared to the "full" avr32 development board.  The cpu has a D/A converter, full LCD controller (for a graphic LCD, and someone has posted how to use the LCD from a Sony PS with this).  The board also has two 100mb ethernet ports, a usb 2.0 port (slave), as well as 2m of dynamic ram.

The arm development board does not have a full LCD interface (a simple serial interface for LCD's that already have a controler on them).  It also lacks USB or ethernet, and external ram.

Both have an interface for flash memory.

The avr32 chip is simply a highly intergrated device, similar to the portal-player chips but with Atmel's own cpu instead of an ARM processor core.  It seems to be close to the performance in mips of the arm, but it's only a single core.

The development board would require external boards to be laid out to handle the required glue logic for things like the LCD interface, audio output, keypad interface, and a flash card.  Once the overall design using the processor was fleshed out a new pc board holding just the required circuity could be laid out, and it could be sized to fit a portable audio player.  I would think that Atmel has the footprint for this package already in a format that can be imported into many pc cad packages, so laying out a pc board for a BGA package shouldn't be a problem (though one would have to deal with a board of at least 4 layers).  The board couldn't be 'stuffed' in one's garage, it would have to be outsourced to an outfit that does this things.

I don't think such a player would be cost competitive with anything from Sandisk or Apple, but it should still be in a price range that might make sense for someone that preferred an 'open' device.  Even if it had to be made a bit larger than what's available, there are advantages to that.  Such as room for a battery with a large capacity for long playing time.  Or an LCD display large enough to show video for those of us with more 'ancient' eyes.  And controls that are large enough for the fumble fingered crowd.  (I admit I'm entering 'old-fart-hood').

For an interface, put a touch screen over the LCD, write some creative software and emulate the iPod touch?

[casainho]

Well, AVR32 or not? - I vote for It, because in future there will be versions with USB OTG, more rapid, low power, etc... and we will have full datasheet and GCC-AVR32

My question is, can someone help to port RB for AVR32?, in this case, using a $100 dev board, with all hardware documented and a GCC port for AVR32? - I can buy the board to test but I am not able to port RB - I hope to learn in the process...

In the next days I will dig the at32ngw100 dev board, try to know what can be done and what hardware is needed do add for have a simple player. One thing is a display.

About PCBs and assembly ICs, I would let that for future thinking, in some way that must be done. Who knows If I can have some made in the company where I work - We have material and machines, but we don't have the project nor we have knowledge to do that.

[Bagder]

The person(s) who'd do the port would most likely need a board as well, and if you tailer the port to the specific board you will need to make your final design pretty much identical to the dev board.

Does the dev board even come with buttons, LCD and nand/disk ?

[casainho]

The person(s) who'd do the port would most likely need a board as well, and if you tailer the port to the specific board you will need to make your final design pretty much identical to the dev board.

Bagder, developers at RB can buy their own hardware or they rely on others offers?

If at32ngw100 dev board is low cost, made by professionals, I would copy/use the circuits of dev board.

Does the dev board even come with buttons, LCD and nand/disk ?

I will dig the board info to know what needs to be add for a for have a simple player. I would appreciate help here

Board comes with 32 MB SDRAM, 16 MB Flash (8 MB serial and 8 MB parallel), SD card and USB. It misses LCD, buttons (should be very ease to add), DAC?? I don't know about it.

Here is an image of the board:

http://avr32linux.org/twiki/bin/view/Main/ModifyTheNGW100

[scharkalvin]

LCD interface on NGW100.  Here's how:
http://dma.elektroda.net/projects/ngw100_ext_lcd/ngw100_ext_lcd.html

The LCD for this guy is about $50.  If someone can copy the pcb and get some made
(need to add header breakouts for some kind of keyboard and AF amp to the D/A on the main board) this would be a good way to start.  Probably talking about $200-$250 out of pocket for the dev board and the i/o board + LCD.  Maybe someone could get a deal on the LCDs if enough people signed up to buy one.

Atmel sells a jtag interface for $300 and avrstudio for the avr32 RUNS ON LINUX! (also windoze)

[casainho]

LCD interface on NGW100.  Here's how:
http://dma.elektroda.net/projects/ngw100_ext_lcd/ngw100_ext_lcd.html

The LCD for this guy is about $50.  If someone can copy the pcb and get some made
(need to add header breakouts for some kind of keyboard and AF amp to the D/A on the main board) this would be a good way to start.  Probably talking about $200-$250 out of pocket for the dev board and the i/o board + LCD.  Maybe someone could get a deal on the LCDs if enough people signed up to buy one.

Atmel sells a jtag interface for $300 and avrstudio for the avr32 RUNS ON LINUX! (also windoze)

I was not expecting the $300 jtag for developing - Is there a cheap way to develop and debug?
I am lucky because I use in my work a JTAGICE mkII for programming and debugging AVR8 which looks like works also for AVR32.

That LCD is very expensive! does we need a display like that? - I would be happy with one black and white, AND with serial interface, which we will win simplicity wiring, so less trouble, less difficult.

[scharkalvin]

The jtag would probably only be needed to get the flash on the dev board to the point where we had a working tftp boot loader via ethernet or USB (do we really want a tcp/ip stack inside rockbox?  Well actually maybe that might be a good idea for file transfer)  Debug could be via a network gdb, but this would require a gdb interface to be written and linked with the software being developed.  (Hopefully somebody here has used gdb in a cross developement setup.)

Atmel DOES discount those jtags to development houses that buy enough of their cpu chips.  (I should inquire at work about this, I might be able to get one for myself at about 1/2 that price if lucky).  There is also a GNU project to develop an open source clone of that jtag, at least for the AVR 8 bit family. I don't know the current status of it and if they are working on something for the AVR32.  Also note that the Linux project on this board is to the point where the jtag isn't needed, they are doing all debug via networked gdb.

The color LCD is probably the way to go, it's what's expected in players of this type.  Similar displays show up surplus from time to time, but the $50 price is actually not unreasonable for something of that quality (1/4 VGA resolution 24 bit color).  Still a cheaper color display (cell phone surplus?) can probably be found.

[casainho]

The jtag would...

About JTAG, It's no problem for me, but It would be nice to have a cheap way. I think that is important to make a cheap and possible DIY player, even using a dev board - with this will be easy to attract new developers.

The color LCD is probably the way to go, it's what's expected in players of this type.

I don't agree with you on this issue. I think that is important to make a first version as a prof of concept, and that should be simple, quick and cheap. I would prefer an old technology of LCD, cheap and with simple connection to board, for no need to design a PCB, just use about 5 wires.

I was seeing another dev boards, there is one for $130, atevk1100, that have one LCD, but it's 4x20 chars - could It be used? - this board also have joystick, buttons, and this AVR32 have USB Device Firmware Upgrade.

[scharkalvin]

atevk1100

That's not the same cpu.  I'm not sure it has the flash disk interface nor the A/D hardware. Atmel makes two families of avr32 cpus. The one you quoted is the smaller, less powerful one. (won't run Linux).  We REALLY want to use the AP7000 family!

If you want to get the "more important" bits working first, sure use a common 4x40 character lcd first but you won't have much in a WPS screen.  Still the early players used this kind of interface.  Cell phone graphic LCD's are available surplus cheap as well.  Look here: http://www.goldmine-elec-products.com/products.asp?dept=1039 , here: http://www.sparkfun.com/commerce/categories.php?cPath=76, and here:
http://www.allelectronics.com/cgi-bin/category/365/LCDs_(Liquid_Crystal_Displays).html for cheap lcd displays.

[casainho]

atevk1100

That's not the same cpu.  I'm not sure it has the flash disk interface nor the A/D hardware. Atmel makes two families of avr32 cpus. The one you quoted is the smaller, less powerful one. (won't run Linux).  We REALLY want to use the AP7000 family!

Ok, lets stay with at32ngw100 dev board and AP7000.

I would go for Color LCD 128x128 Nokia, because It's cheapest graphic LCD, there is a lot of information, code examples, easy to buy and because have serial interface!! - there will not be need to do a board for LCD.
http://www.sparkfun.com/commerce/product_info.php?products_id=569

So, what's need more? We have microcontroler, SRAM, FLASH, USB, LCD, buttons. What about DAC?

[saratoga]

The person(s) who'd do the port would most likely need a board as well, and if you tailer the port to the specific board you will need to make your final design pretty much identical to the dev board.

Bagder, developers at RB can buy their own hardware or they rely on others offers?

If at32ngw100 dev board is low cost, made by professionals, I would copy/use the circuits of dev board.

The developers for a port are the people who own the hardware, meaning you!