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

[casainho]

oh no!! how could we miss the audio jack. we keep missing something or the other. audio is very crucial and should come bundled with the dev board.

I don't think that audio should come bundled with the dev board. As I see here: http://www.mikrocontroller.net/articles/Bild:TLV320AIC23B_Connection.png, it's not difficult to wire. And as I see in DSPdap, there are just 10 wires, 8 from MCU + 2 for power. I believe that speed communication is not higher so we can attach audio DAC in an outside board. Also pin size of that IC is ok, for solder by hand, I think.

We will need another board for audio DAC, buttons and LCD module :-)

I made a diagram of the dev board. At red the main dev board and at green an other that we will need to made by hand. This is just a minimum system to have Rockbox ported and to show that It can be done.



EDIT on 18.01.2007_21h06:
I got today the Color LCD 128x128 Nokia from Sparkfun! also the connector, which should be very difficult to solder. When I bought the LCD, the Carrier Board was out of stock... today they already have it again!! So I will buy a carrier board instead of trying to solder the thin wires.

SparkFun also sells a ARM JTAG Programmer/Debugger which looks ok, at least is the same 2x10 pins connector as in dev board. Should I also buy this ARM JTAG Programmer/Debugger from SparkFun?? $30: http://www.sparkfun.com/commerce/product_info.php?products_id=275

I am studding the dev board and the possible connections to LCD and DAC. I let the USB out because there is no code in Rockbox to work with USB, files should be put on SD flash card - there is code for SD flash card in Rockbox, at least It is working on Sansa E200 V1.

EDIT on 19.01.2007_9h26:
I were talking on IRC and I found that the IriverH10Port uses also a 128x128 color LCD, should be nice to look at that code as example :-) Some words that were written on IRC:

The size of the LCD isn't important, it's the format it stores the pixel data in. So far, all our colour LCD targets are using the same high-level framebuffer drawing code because the format is the same (or very similar).
LCD_WIDTH and LCD_HEIGHT are simply #defines.
Each pixel is stored in two adjacent bytes, in RGB565 format, moving horizontally from the top-left to bottom right.
Some devices require that in little-endian format, others in big-endian, but that's handled with macros.
But I think that's more or less standard for colour LCDs, or at least all the ones in Rockbox devices so far.
You may want to consider mono or greyscale LCDs though - they have the advantage of being much easier to read without backlight.
Some colour LCDs can't be read at all without backlight.
The point is that any backlight uses power, and it's nice if an LCD can be read without it.
one of the points is that in many cases, backlight is a waste of energy, when you would normally be able to see just fine without backlight on a manachome/greyscale device

EDIT on 20.01.2007_19h43:
I defined today all the connections between LCD module and the maind dev board. I put some pictures on TWiki.

Bootloader or not bootloader? reading the some TWiki pages about develop a new port, write a bootloader is the first task. I tried to figure out if there will be the need of a bootloader and talked on IRC, It looks like will not be necessary because the AT91SAM9260 already have one in his ROM - It can bootload by USB, serial port, JTAG and others options.  About that bootloader: The SAM Boot Assistant (SAM-BATM) software provides a means of easily programming different Atmel ® AT91SAM ARM ® Thumb ® -based devices. It runs under Windows®2000 and XP.
Communicating with the target device may be done through an RS232, USB or JTAG link.

Ready more here: http://www.atmel.com/dyn/resources/prod_documents/doc6132.pdf

I found on RB source a driver for the audio DAC IC, the TLV320 :-) - http://svn.rockbox.org/viewvc.cgi/trunk/firmware/drivers/audio/tlv320.c?revision=&view=markup
It's used one the IaudioX5 at least: http://www.rockbox.org/twiki/bin/view/Main/IaudioX5HardwareComponents#TI_TLV320AIC23B_Audio_Codec_with

However it uses I2C and we must use SPI, so, at least no all the code will need to do from scratch for the audio DAC :-)

[KammutierSpule]

Viva people!

My first post here!  

I'm a robotic entusiastic and I've found "rockbox" because I was looking for something hackable and small with great CPU power, that is something missing in hobbyst robotics, firstly because in small robotics projects you dont need suck great power. But, I'm trying move next, and what I was looking for is for something small that can host a webcamera or a CCD or something like a phonecamera.

Actualy, in robotics, the only options you have to use cameras, are use some kind of costly SPI or embeded board camera ( a fast search in google found this one http://www.active-robots.com/products/accessories/cmucam.shtml by  £117.49 (about 227 dolar) )
or you can use small and cheap USB webcams to your robotics, at cost, that you need a PC host and processing computer and the small you can get is something like a miniITX,nanoITX, that you can't get a system work for less than about 300 dolars.

I try find someking of similiar work as rockbox for webcams or digitalphotomachines but seams to be none, sadly because I found that some cheap and old have good and fast chip processing that maybe can be used for the propouses i'm talking.


Then, at rockbox main page, I found in the last wiki activity and fond JorgePinto, thats actualy a Portuguese name. As I'm a Portuguese too, its not usually find some on this kind of scene... I search a little more and get in conclusion that he is from same stat of me, actually live about 22Km near my home town. ehhe

I've talked with him a little about project and I will post here some ideas to you discuss.

I've read almost all posts in this thread, firstly, I'm not so optimist as some of you are, and somethings about it has already said.

So, I think you dificult will get some small, easy done, all embedded circuit/PCB that you can put in a small plastic and people use very happy in his poket and show to his friends and they want one too. So, as some one could think, its impossible for our common normal people make a usable portable nice player, then as said before, using our best practices to manufactur some kind of player, it will be allways more expensive and tecnical less powefull than any "last year" player.

I found this project usefull if people can learn from it, also developers, and users that can get more inside electronics and maybe can try use a endly project board to make your own tests and firmwars. Actualy, the sadly thing is that a board for one player like it, you couldn't solder it at home :/

My hope thing is, if you can make a board player like we are talking about, is that have some powerfull computation as cheap, small board also with expansible capacities, so that can be used in other projects or expansions!

The expecification (CPU,ROM,RAM) seams ok to my needs, you will add a DAC and something else. Then, my next ideas are:


.Leave some room space to solder any new connector to not used pins and bus or
.Leave some expantion socket that you can latter add something else.
.USB host capabilities will be a step ahead, for my webcam Ideas : )
.Seams AVR have CCD sensor interface capabilties make it open too : )
.LCD seams nice for this aplication, but 128x128 wont be for other, make planed somehow to expand this.
.Think that will be nice to plug power in board, to dont need use the battery charger.

Other ideas will come.

I think if you make it a little more interface acessible, you and board manufact. will have a wide range of users.

Will be nice have a board that can be a robotic processor unit, speach processor :>, music player, and so on!

I sugest casainho to put in wiki page some table with this ideias and other as possible specifications and wants for this. Put a rate in each one like: "Essencial, Important, Desirable"

and...

Have fun!  

KammutierSpule
Mário Luzeiro



EDIT: 23 Jan 2008
The nordic RF chip sugested by Olimex seams to be really a nice chip, I've alreade study datasheet because I'll use it in my work. But, actually it gives you only 2Mbit/s that shoulndt be too much if share large musics, but will be nice to ear remote music, share playlists, games?, wallpapers, and for me, also robotics hehe

This chip consume about 12mA at max power and 13mA in reciving. In deep sleep mode is consume less than 1uA.

[casainho]

.Leave some room space to solder any new connector to not used pins and bus or
.Leave some expantion socket that you can latter add something else.
.USB host capabilities will be a step ahead, for my webcam Ideas : )
.Seams AVR have CCD sensor interface capabilties make it open too : )
.LCD seams nice for this aplication, but 128x128 wont be for other, make planed somehow to expand this.
.Think that will be nice to plug power in board, to dont need use the battery charger.

I sugest casainho to put in wiki page some table with this ideias and other as possible specifications and wants for this. Put a rate in each one like: "Essencial, Important, Desirable"

EDIT: 23 Jan 2008
The nordic RF chip sugested by Olimex seams to be really a nice chip, I've alreade study datasheet because I'll use it in my work. But, actually it gives you only 2Mbit/s that shoulndt be too much if share large musics

I am busy right now, I am having pleasure in read, define, working in the schematics. On the right time I will put on TWiki that information, which I thing are good ideas :-) - maybe someone can write them :-)

About wireless connectivity, I will work on the idea after the 1st version of the player. I would desire something to connect with portable devices for sharing files, the player will not browse the internet to download files but It should connect to others devices that can do that, IMO.

I draw today the schematic - in KICAD :-) - of the secondary board, which will need to be made by hand! - I will complete that schematic for buttons, domonoky suggested some kind of resistors and one ADC for buttons. I will also complete the schematic with information about pins. I attach the schematic here :-)
- http://www.rockbox.org/twiki/bin/viewfile/Main/RockboxPlayerV1?rev=1;filename=secondary_board.jpg
- http://www.rockbox.org/twiki/bin/viewfile/Main/RockboxPlayerV1?rev=1;filename=rockbox_player-24012008.sch

Sorry, but I want to use that SAM9-L9260 dev board and not spending more time to find one cheaper that that! - we have a lot examples from Atmel to use the audio stereo Codec with I2S and I2C, to use the SPI link for the LCD and we have already drivers on RB for that ARM core :-)

domonoky started editing the TWiki page and giving information about hardware :-) and I am being talking on IRC... also studding the RB code... talkind on IRC with Bagder about how to boot the system...

[KammutierSpule]

About wireless connectivity, I will work on the idea after the 1st version of the player. I would desire something to connect with portable devices for sharing files, the player will not browse the internet to download files but It should connect to others devices that can do that, IMO.

the wireless will add about 25mm x 25mm more space for transciver plus the antenna that can be in circuit or maybe a wire ?
Olimex have a demoboard based in the chip.

[casainho]

About wireless connectivity, I will work on the idea after the 1st version of the player. I would desire something to connect with portable devices for sharing files, the player will not browse the internet to download files but It should connect to others devices that can do that, IMO.

the wireless will add about 25mm x 25mm more space for transciver plus the antenna that can be in circuit or maybe a wire ?
Olimex have a demoboard based in the chip.

+ plus price + time + software, which I think there is not software for RB! - leet's see if a 1st version of this hardware will get attention of developers, to work more on this idea of Free/Open hardware. Anyway, to develop, we can use the dev boards, I think we should not put in production hardware not tested, without RB working on that.

NOTE: I did update the schematic on TWiki page.

[scharkalvin]

Will somebody put together a complete BOM with cost of parts and links to where to purchase?
If enough people are interested maybe a group buy package might be available and a better
price could be had from the suppliers (well I can hope)?

[casainho]

Will somebody put together a complete BOM with cost of parts and links to where to purchase?
If enough people are interested maybe a group buy package might be available and a better
price could be had from the suppliers (well I can hope)?

I am working in external board, after finish, I will do that. Expressive parts in terms of price, are main board, which will be bought on Olimex. After the LCD + carrier board on SparkFun. I don't know If there will be the need to buy a JTAG cable in SparkFun... I bought one, It's my first time... Others parts are just resistors and capacitos, plus the audio codec which can be a sample from TI. I plan to make the external board on the company were I work, for me and maybe 10 more units, which I will try to assembly, with all components, and send by mail to developers.

I just would like to have a discount from Olimex, however, I will not do that! Because is a company from Bulgaria, which I think is a poor country then Portugal. I know a person from Bulgaria that told me that works about 10-12 hours a day... I think the price of the board from Olimex is a fair price. IMO, ipods and things like that are really cheap because of the low prices of hard labor work on China.

TIME: I think that we will stick with same hardware for at least 2 years. We can use the same dev board for develop thins like hard drive support, USB stack, or wireless, etc... - so, buying that dev board will be good to work on RB, I hope.

I were on IRC talking, here are some things about USB on Rockbox and wireless:
- I would like to know if RB work with USB? and If it works with some kind of wireless? - I am asking this because of planing hte hardware for RB player...
- Rockbox has no USB stack or no wireless.
- Rockbox works with USB under certain circumstances.
- The players it works on have some form of hardware USB-ATA bridge. Ones where we need a software USB stack, it doesn't work with yet
- So, It's a good idea to make an hardware with USB, or not? and the same question about wireless like bluetooth...
- adding any sort of wireless connection would require adding a ton of support to Rockbox
- okok, so, about connectivity, what a hardware player for Rockbox should have?
- usb
- what can you tell-me about the USB on the Atmel AT91SAM9260? - I would like to know If it have some kind of USB-ATA inside or not...
- it needs a usb stack
- at least, will the SD card work, on that board?
- sure, with a suitable driver it should
- so, the driver in RB for Sansa SD card will not work? - what are the difference? - hardware?... I am lost... :-)
- the (micro)sd thing in rockbox is for sansa, I don't know how suitable that is for your setup. should be mostly the same of course
- Unless you have the exact same hardware, attached in the exact same way, you'll always have to do some, possibly a lot, of new code.

[cool_walking_]

When you guys decide to buy something, I'll chip in for one or two. I know next to nothing about hardware, so it could be a good learning opportunity if you guys let me bug you every time I break something.

[Bagder]

- Rockbox has no USB stack

Yes it does. although still not properly functional on the Sansa/PP hardwares for which it only so far has been targeted at.

[casainho]

When you guys decide to buy something, I'll chip in for one or two. I know next to nothing about hardware, so it could be a good learning opportunity if you guys let me bug you every time I break something.

Nice to know that you would like also to jump on the wagon :-)

All hardware will be documented, we are just selecting ICs with full datasheets and most of them have application notes, examples :-)

- Rockbox has no USB stack

Yes it does. although still not properly functional on the Sansa/PP hardwares for which it only so far has been targeted at.

So, after the chat, I will add USB to the list to develop software for. Would be nice to have developers with experiences to work on that.

About bootloader, Bagder told me that would be possible to use the 512MB NAND Flash to have a bootloader and also other part of the flash with a FAT32 file system. Bootloader will initialize hardware, mount FAT32 file system and init RB application thats reside on FAT32 file system - thats the idea I have :-)

[Bagder]

I said it can boot from NAND since the data sheet for the MCU says it can. Separating the flash in several partitions, like one for the boot-loader and another for a FAT filesystem should be trivial.

However, which I've tried to get through on IRC, since the planned player hw has no NAND flash of its own (other than replaceable memory cards) I think it is a bit of a waste to write a special boot procedure for the dev board only. I would then probably instead focusing on booting the devboard from USB to make it easier to develop with faster round-trips.

I am however not at all sure about which of these hardwares you refer to when you speak about lots of stuff in this project, and I'm certainly not sure which or if both of these that have the serial NOR flash.

Also, I'd suggest you go for building and using u-boot as bootloader as I'm quite sure that's already ported and working fine on the AT91 SAM9 targets. That will also allow you to load Rockbox over ethernet (TFTP) while developing and that'll be very convenient.

[casainho]

I said it can boot from NAND since the data sheet for the MCU says it can. Separating the flash in several partitions, like one for the boot-loader and another for a FAT filesystem should be trivial.

However, which I've tried to get through on IRC, since the planned player hw has no NAND flash of its own (other than replaceable memory cards) I think it is a bit of a waste to write a special boot procedure for the dev board only. I would then probably instead focusing on booting the devboard from USB to make it easier to develop with faster round-trips.

I am however not at all sure about which of these hardwares you refer to when you speak about lots of stuff in this project, and I'm certainly not sure which or if both of these that have the serial NOR flash.

Also, I'd suggest you go for building and using u-boot as bootloader as I'm quite sure that's already ported and working fine on the AT91 SAM9 targets. That will also allow you to load Rockbox over ethernet (TFTP) while developing and that'll be very convenient.

I will read about this things later. I am a bit loose here :-)

I did define now the connections between external board and MCU, and main dev board - I2C bus, I2S bus and SPI bus. I hope that are all ok, if someone can verify, great!

Next I will define the hardware for buttons and I will use the suggestion of Domonoky, with one ADC and resistors: http://www.scienceprog.com/interface-multiple-keys-with-one-wire-and-save-pins-of-mcu/
I must define the number of buttons, can anyone suggest a good number and function of each one? - I did sketch but I don't know If are right: 1º Options; 2º Menu; 3º Play/Pause; 4º Up; 5º Down; 6º Left; 7º Right.

After having all hardware defined, I will try to draw and assembly the external board and at the same time starting working on code - bootloader :-)

[scharkalvin]

yet another development board.
They have some interesting but expensive add on's

http://www.littlechips.com/sbc_main.htm

[casainho]

Chating on IRC, I got this information: 8 total buttons, 4 direction buttons (up/down/left/right), select, menu, play/pause and stop. Up and down buttons typical acts as volume up and down.

I will now start the calculus for the schematic for this 8 buttons and later put final information on TWiki page 

[scharkalvin]

8 total buttons, 4 direction buttons (up/down/left/right), select, menu, play/pause and stop. Up and down buttons typical acts as volume up and down.

This pretty much is the same as the Gigabeat (my favorite ui) except that the gb also has separate controls for volume, but the up/down buttons also control volume on that so the only advantage is that the volume control is available on the side of the unit when it is closed up in a case.

The stop button could also be used as a power down / power up / reset button.
Press and hold while powered off turns it on, press and hold while powered on turns it off, very long press and hold resets.  

Missing is a slide switch for lock.