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

[Sonic]

Sure, the OLED display looks sweet, but... 128x128? In my opinion, 128x128 would only be good for music. And as RockBox can be used for video and photo viewing, and for playing games, shouldn't the screen at least meet the industry standard of 320x240?

[scharkalvin]

shouldnt' the screen at least meet the industry standard of 320x240?

Well 128x128 would be good enough for proof of concept.  But you are right, a 320x240
(or 240x320) would be better.  The latter gives more room for text info and can be rotated
90 degrees for video.

[casainho]

Sure, the OLED display looks sweet, but... 128x128? In my opinion, 128x128 would only be good for music. And as RockBox can be used for video and photo viewing, and for playing games, shouldn't the screen at least meet the industry standard of 320x240?

Please read the page of the project: http://www.rockbox.org/twiki/bin/view/Main/RockboxPlayer

One objective of the project: Good quality hardware audio player and recorder - no video player or game console;

[mzandrew]

oled display
can we have datasheets of the oled display? how many colours does it support?

It's 18 bit color, so 262,144 or so.

cashainho's correct, it's sparkfun's oled display.

Datasheet for the controller:  http://www.sparkfun.com/datasheets/LCD/SSD1339_1.7.pdf

spi flash or NAND flash

Rockbox will be stored in spi flash and be copied to ram upon bootup. This means that it will be necessary a larger SDRAM value?

Why not NAND flash? We can have a 8Gbit (1GByte) NAND flash for $16. This can serve as firmware space as well as media storage.
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=557-1373-1-ND
Linux can also be used. you can literally swim inside here.
It can also save you from buying an SD card.

I want to save as much space as possible on the main board, so I opted for spi flash because it comes in an 8 pin package.  And you can only get spi flash (dataflash) that's a few mebibytes in capacity.

I'm not opposed to using soldered-down flash for another rockbox player, it's just this first one I want to be just sd cards.

Mobile SDRAM
Yes, unfortunately these low voltage (1.8V) SDRAMs are only available in BGA package. So we have to stick to 3.3V SDRAMs.

The atmel at91sam9260 can use 3.3V or 1.8V ram on the external bus interface.  It really is just a question of being able to solder a BGA without the great expense of having a company assemble it for us.

As I told casainho via instant messaging, I have access to an infrared lamp BGA rework machine, so it might be possible to do it, but I still would like this project to result in a board that an advanced amateur electronics hobbyist can assemble himself without any expensive tools.

[mzandrew]

Could you post more info about your oled clock project?

Here's the write-up for the project I submitted as part of my class last semester.  It has gobs of details:
http://arm7-oled-clock.googlecode.com/files/arm7-oled-clock-project-write-up.pdf

You seem to have PCB design experience. which tools do you use?

I used the unregistered version of Eagle.  I found it to be very good.  It has a few bugs / imperfections, but it doesn't crash.  I suppose I'll have to give them the $50 registration fee if we actually make a commercial product out of this.  

[mzandrew]

Sure, the OLED display looks sweet, but... 128x128? In my opinion, 128x128 would only be good for music. And as RockBox can be used for video and photo viewing, and for playing games, shouldn't the screen at least meet the industry standard of 320x240?

shouldnt' the screen at least meet the industry standard of 320x240?

Well 128x128 would be good enough for proof of concept.  But you are right, a 320x240
(or 240x320) would be better.  The latter gives more room for text info and can be rotated
90 degrees for video.

I would love to use a higher resolution display, but not a physically larger one (I want this player to remain small).  Anyone know of a source of OLED display modules that are about 1"x1" and 256x256 or 320x240 or so?

All I've found is the ones from sparkfun (univision and 4dsystems).  Anyone want to expand on this list of OLED module (display+controller, but without serial backpack) suppliers?

There's a 160x128 module (http://www.sparkfun.com/commerce/product_info.php?products_id=8543), but it's $108 and has a serial interface that won't be used.

I'm also not opposed to eventually making another circuit board for a different rockbox player that would have a much larger/higher resolution screen and use a 2.5" hard drive so you could store ALL your music on it.  But that's not the goal of this circuit board right now.

[Llorean]

I'd say the minimum screen size *I* would recommend is 220x176 (H300, iPod Photo, Sansa e200). Mounted portrait is my personal preference. This offers (to me) enough space to fit a lot of information with a small font, or a few very important lines with a very large font, and is about the right point of flexibility (in my view).

[spark]

Here's the write-up for the project I submitted as part of my class last semester.  It has gobs of details:
http://arm7-oled-clock.go...lock-project-write-up.pdf

I like your work. The accelerometer idea is cool. i had a clock which used a similar idea and we had to scratch our heads for some time to find out how to change modes on it.

the oled display is great. it uses a SSD1399 controller which has both parallel and serial interfaces.  

I want to save as much space as possible on the main board, so I opted for spi flash because it comes in an 8 pin package.  And you can only get spi flash (dataflash) that's a few mebibytes in capacity.

I'm not opposed to using soldered-down flash for another rockbox player, it's just this first one I want to be just sd cards.

Components can be mounted on both sides of PCB. It is always handy to have larger firmware space. You can have on board NAND flash and SD card too. SPI flash will limit the usage of the board in the long run. if you can solder the uC then soldering the NAND chip should not be an issue.

PCB tools
The unregistered feature limited version of Eagle will not be sufficient for our project.

I tried using Kicad. The schematics tool is good but you can't have more than one sheet. The pcb editor is ok but there are many limitations. you cannot undo any operation and not all operations have keyboard shortcuts.

I also tried gEDA tools on Linux. This is very unfriendly for new users because the schematics, netlist generator, pcb editor, etc are not closely coupled. you need to do a lot of manual intervention and scripting in between. the pcb editor is better than that of Kicad though.

i will try the svn version of kicad to see if it is any better.

[casainho]

I'm also not opposed to eventually making another circuit board for a different rockbox player that would have a much larger/higher resolution screen and use a 2.5" hard drive so you could store ALL your music on it.  But that's not the goal of this circuit board right now.

I think you should define very well what you want for this version, on TWiki page, specially what will player do and do not. I saw your update, great!!

Also looks like to me that you want to make a perfect system in just one shoot! Remember that you and all others interested developers will be able to continue this work!! There is no need to make it perfect at the very first time.

I will try to help finding components, prices, datasheets. When you have all defined I can focus on start reading about software, finding drivers in Rockbox, etc.

A suggestion, as I think this player will also serve as a learn platform for all hackers in Rockbox, leave pads for free pins of the MCU and all that you think interesting. And JTAG pins for sure.

Ambient light sensor? - whats for? can you explain? - I saw it is with a red line line battery, what thats mean? :-)

[spark]

We should merge RockboxPlayerB and RockboxPlayerV1 both are the same with different names. I think we can stick to V1, V2 naming convention.

Matt i appreciate your efforts on the TWiki, but i think the tone in the writing should not contain anything which indicates that one person is building it single handedly.

[casainho]

We should merge RockboxPlayerB and RockboxPlayerV1 both are the same with different names. I think we can stick to V1, V2 naming convention.

Matt i appreciate your efforts on the TWiki, but i think the tone in the writing should not contain anything which indicates that one person is building it single handedly.

I would wait for answer from Matt, before merge. Because Matt must do that prototype for his school project, and maybe we wants to go "alone" to get it done in time.

Anyway, we can win a lot with Matt work. Spark, you can also start drawing "your" schematic. I will help everyone but we will feel the need to merge, to join our energies. Spark, you can also wait for Matt finish and after we can start to work on another version.... eheh, a lot of ideas :-)

[spark]

Anyway, we can win a lot with Matt work. Spark, you can also start drawing "your" schematic. I will help everyone but we will feel the need to merge, to join our energies.

Casainho, There is nothing such as "my" schematic or "your" schematic. The beauty of working together is to have "our" schematic. it doesn't matter who does the drawing. A good schematic is a result of many inputs from different people.

[scharkalvin]

As I told casainho via instant messaging, I have access to an infrared lamp BGA rework machine, so it might be possible to do it, but I still would like this project to result in a board that an advanced amateur electronics hobbyist can assemble himself without any expensive tools.

Schmartboards has a prototyping system for BGA chips.  Anybody every seen these?
http://www.schmartboard.com/index.asp?page=products_bga

[casainho]

As I told casainho via instant messaging, I have access to an infrared lamp BGA rework machine, so it might be possible to do it, but I still would like this project to result in a board that an advanced amateur electronics hobbyist can assemble himself without any expensive tools.

Schmartboards has a prototyping system for BGA chips.  Anybody every seen these?
http://www.schmartboard.com/index.asp?page=products_bga

Looks good for prototypes, however Matt(aka mzandrew), said "I want to save as much space as possible on the main board" so I think it will not help.

We need help from a company that have resources to assembly BGA! We can't go to talk with them without a working prototype!

I asked "Ambient light sensor? - whats for? can you explain?" - I already know after reading http://arm7-oled-clock.googlecode.com/files/arm7-oled-clock-project-write-up.pdf

[scharkalvin]

We need help from a company that have resources to assembly BGA! We can't go to talk with them without a working prototype!

That's a typical catch22.  If you design a circuit using prototype boards (which will be larger than
the desired end product) you can prove your circuit schematic and software concept, then layout the final board and have it assembled in larger numbers (and finish the software design).