Hardware Development

[Polk1986]

As this is an open source handheld, I was wondering how many people are interested in hacking the hardware? I for one would like to change the TV out to VGA out and add a cellular chipset so I can take a Pandora with me and not need another device. Along these lines, does anyone know what sort of space limitations we will have inside? Are the board and battery going to take up the entire case or will there be a few crevices and crannies to pack some extra goodies into if we want?

If you are also interested in adding hardware capabilities to the Pandora when it comes out, I thought we could compile our ideas here and talk about some possibilities available due to the open nature of the Pandora.

 

[mindlord]

You're not the first one to want to try and cram VGA out and a cell phone in there. Sadly, you're going to be hard pressed to find room for just one of those, let alone both. Every nook and cranny is filled with gooey Pandora goodness. Any major feature addition, like VGA or Cell Phone ability is going to take some case modification.

Also.. I hate to be a bearer of bad news, but VGA out has been discussed already. Please believe me when I say it's not worth pursuing. It is not possible because the LCD is using the lines you would need to create a VGA or DVI or HDMI or any other video source out. You could try to intercept the signal before it gets to the LCD Controller, but that is nigh impossible. It would involve cutting traces, and all manner of nastiness.

S-Video is all we will ever have on the secondary output because all the RGB to Compsite/Chroma conversion is done inside the OMAP chip itself, and the individual RGB component lines are not exposed to the outside world.

 

[Exophase]

It's not an open source handheld, it's a handheld that's meant for running open source software. Unless the Pandora team has changed or will change their mind then I don't think schematics/layouts/etc are going to be open, beyond what's present on the EXT port. The pivotal OMAP3530 chipset isn't 100% documented either, with most details of the SGX and "video accelerator" blocks being left undisclosed.

The team probably (rightfully) doesn't want someone else cloning their design verbatim without having to work for it first.

 

[atomicthumbs]

I hope you're happy with a big lump sticking out of or taped to your Pandora, then.

 

[Kramy]

USB HSDPA. Probably the least painful way to go.

 

[Polk1986]

Also.. I hate to be a bearer of bad news, but VGA out has been discussed already. Please believe me when I say it's not worth pursuing. It is not possible because the LCD is using the lines you would need to create a VGA or DVI or HDMI or any other video source out. You could try to intercept the signal before it gets to the LCD Controller, but that is nigh impossible. It would involve cutting traces, and all manner of nastiness.

That's more or less what I thought would be the case. I probably won't mess with that then. However, I feel with a certain degree of case-modding, I believe the cellular chipset is not impossible, although it won't fit in the stock unit. I am OK with this. Thanks for all your responses, as they're very helpful. I only recently discovered the Pandora and can use all the info I get.

 

[RalpH_himself]

I heard that the layout (and a few documentation) of the pads for custom extensions will be made public, when and where will this be?
I simply can't await to start planning some modifications!
-r


edit:
btw, does anyone know, what the maximum sampling rate of the audio input is, and how it could be improved? I'm thinking about an oscilloscope application right now :rolleyes:

 

[kurtken71]

Is the UART1 going to be available somehow? This is the primary debugging serial port for the unit, hard-coded into the SoC for alternate booting.

It would save time scoping the board if we knew where it was, and it's not technically a hack since we're not modding the board - just getting access to it.

 

[Exophase]

Is the UART1 going to be available somehow? This is the primary debugging serial port for the unit, hard-coded into the SoC for alternate booting.

It would save time scoping the board if we knew where it was, and it's not technically a hack since we're not modding the board - just getting access to it.

Yes, boot UART is coming off the ext port and all of the ext port pins will be publicly documented.

 

[mindlord]

edit:
btw, does anyone know, what the maximum sampling rate of the audio input is, and how it could be improved? I'm thinking about an oscilloscope application right now :rolleyes:

The Pandora has a Burr Brown DAC, which is considered to be top-notch. According to this datasheet the sample rate is 48kHz.

Also:
If you check this image you can see the solder pads that are made available.
@kurtiken71: Not sure about UART1, but there is a JTAG connector (the pads anyway) available. Also a serial connection is available on the EXT connector.

 

[kurtken71]

Is the UART1 going to be available somehow? This is the primary debugging serial port for the unit, hard-coded into the SoC for alternate booting.

It would save time scoping the board if we knew where it was, and it's not technically a hack since we're not modding the board - just getting access to it.

Yes, boot UART is coming off the ext port and all of the ext port pins will be publicly documented.

ossim!

 

[RalpH_himself]

The Pandora has a Burr Brown DAC, which is considered to be top-notch. According to this datasheet the sample rate is 48kHz.

Well, thanks for the infos, but on the brief summary on top of that link, I see only outputs and no inputs. Which is actually logic, if you are talking about DAC. But I was wondering about ADC, a.k.a. line IN. Or did I miss something?

 

[fuzzypinkunicorns666]

The Pandora has a Burr Brown DAC, which is considered to be top-notch. According to this datasheet the sample rate is 48kHz.

Well, thanks for the infos, but on the brief summary on top of that link, I see only outputs and no inputs. Which is actually logic, if you are talking about DAC. But I was wondering about ADC, a.k.a. line IN. Or did I miss something?

I believe that the TWL4030 is being used for the line-in. But good luck finding an actual datasheet for it, the best I could find was a little brochure for it. I doubt it'll be sufficient for what you want, it's probably 48khz as well.

 

[MWeston]

The Pandora has a Burr Brown DAC, which is considered to be top-notch. According to this datasheet the sample rate is 48kHz.

Well, thanks for the infos, but on the brief summary on top of that link, I see only outputs and no inputs. Which is actually logic, if you are talking about DAC. But I was wondering about ADC, a.k.a. line IN. Or did I miss something?

Line inputs (shared with microphone inputs) are in the TI power management chip: http://focus.ti.com/docs/prod/folders/print/tps65950.html

 

[maiden]

add an FPGA and ALOT of dev-time then you can get a VGA port or any other port you want,
Easiest way to get a vga out is to use a "usb to VGA", but that might also involve some coding.
http://ubuntuforums.org/archive/index.php/t-260863.html <- usb to vga with linux support
http://www.ravirajtech.com/USB-GSM-GPRS-FAX-Voice-Modem.html <- usb to gsm with voice support (linux drivers?)

if you are a bit more hardcore:
http://www.opalkelly.com/products/xem3005/ <- usb to FPGA

 

[infrared]

Not sure if this will work... BeagleBoard is an OMAP3 based system very similar to the Pandora. The BB has S-video and DVI (through hdmi port). A vga adapter board is available at beagleboardtoys Because I do not have a Pandora board to review I can not say this will work. It would be worth while to investigate but as previous post inform the Pandora board is limited to the LCD and S-video out.

 

[valhalla]

Not sure if this will work... BeagleBoard is an OMAP3 based system very similar to the Pandora. The BB has S-video and DVI (through hdmi port). A vga adapter board is available at beagleboardtoys Because I do not have a Pandora board to review I can not say this will work. It would be worth while to investigate but as previous post inform the Pandora board is limited to the LCD and S-video out.

IIRC the VGA adapter for beagleboard uses the LCD interface, which is not available on pandora because it is taken by the actual LCD.

 

[Rockthesmurf]

I want to mod my Pandora (probably extend the case as well) so I can put a filament inside it, also I would like to have a water cavity in it, but not for water cooling. Finally I would like to have a side pouch for storing tea bags. I am pretty sure the Pandora could then be utilised for some sort of kettle/tea pot combination device. Perhaps this is already the plan for the Pandora II? If not I'd like to make sure I get my royalties if this idea becomes reality, which I am pretty sure it will be based on how good the idea is.

Steve

 

[lulzfish]

Wait, what's a filament? Like a heating element?

 

[OrR]

@Rockthesmurf: You probably want this: http://www.pomegranatephone.com/