Difference between revisions of "RaspberryPiBoard"

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(Accessories & Peripherals)
(Interfacing to Raw LCD Panels)
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* The SOC does not support any kind of analog component video, including VGA, since the SOC is designed for mobile phone use where this would not be a requirement.
* The SOC does not support any kind of analog component video, including VGA, since the SOC is designed for mobile phone use where this would not be a requirement.
* Composite and HDMI outputs can not be used at the same time (one or the other.)
* Composite and HDMI outputs can not be used at the same time (one or the other.)
==Interfacing to Raw LCD Panels==
Nokia N900 has 800x480 DCS LCD [http://e-ditionsbyfry.com/Olive/ODE/ECN/default.aspx?href=ECN%2F2009%2F08%2F02&pageno=5&entity=Pc00502&view=entity (afaik its like DSI, but has build in framebuffer)].
Replacement screen is about ~$40 (~$50 with 4pin resistive touchscreen).
Nokia N8 has AMOLED 360x640 pixels DSI LCD.
Replacement screen is about ~$35, another ~$25 for Multitouch Synaptics T1021A touchscreen (I2C + interrupt IO, no docs/drivers).
Potential LVDS interfacing chips :
[http://www.toshiba-components.com/mobile/data/Toshiba_TC358764_65XBGA.pdf TC358764/5 Display Bridge (MIPI® DSI to LVDS)]
[http://e2e.ti.com/cfs-filesystemfile.ashx/__key/CommunityServer-Discussions-Components-Files/130/3252.DVI_3B00_HDMI_2D00_to_2D00_LVDS-Bridge-Application-Note.doc DVI receiver TFP401A, TFP403, or TFP501 + LVDS transmitter SN75LVDS83B or SN65LVDS93A] (Mentioned earlier fit-VGA is build around TFP401A, probably many more "active" DVI2VGA cables are build the same way) 
I2C/SPI ADC can be used to interface 4 pin resistive Touch Screens, For example [http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00291197.pdf STMPE812A]
===16x2 LCD Displays===
The old-style 2-line, 16-character LCD displays can be commonly controlled over UART, thus providing a cheap way to display values for sensors etc.
==Interfacing to Camera Module==
==Interfacing to Camera Module==

Revision as of 08:39, 16 January 2012

Logo of Raspberry Pi
Please note that the Raspberry Pi wiki pages on this site are a community work, the Raspberry Pi Foundation is not responsible for content on these pages
Please note that the Raspberry Pi isn't released yet - this page is a community work in progress in preparation for the launch

The Raspberry Pi is an ultra-low-cost (~15GBP or 25USD) credit-card sized Linux computer for teaching computer programming to children. It is developed by the Raspberry Pi Foundation, which is a UK registered charity (Registration Number 1129409). The foundation exists to promote the study of computer science and related topics, especially at school level, and to put the fun back into learning computing.

We expect this computer to have many other applications both in the developed and the developing world.

  • Estimated availability (as of 31st December 2011) is end January 2012 for the first batch of 10 000. On 31st December 2011 at 22:00, the Foundation auctioned the first two of ten beta boards on a seven-day auction. The following eight were auctioned on the following days. Initially, there will be shipping from the UK and possibly the US, but will probably expand with local distributors by the second quarter of 2012.



Raspberry Pi Staff will be attending the following events:

The following are general-interest industry events and are not an indication that Raspberry Pi will be attending, exhibiting or speaking at the event. For Raspberry Pi event and speaker schedule, please contact press@raspberrypi.org.

February 2012

July 2012

  • O'Reilly Open Source Convention (OSCON) at Portland, Oregon Convention Center July 16-20, 2012. The Call for Papers is scheduled to be posted in November 2011.

Past events

Discuss: http://www.raspberrypi.org/forum/general-discussion/conferences-and-other-public-appearances


Mock-up of the Raspberry Pi beta board
main article: Rpi Hardware

The first product is about the size of a credit card, and is designed to plug into a TV or be combined with a touch screen for a low cost tablet. It comes in two tastes, A and B, with B having more features. The expected price is 25$ for model A, and 35$ for model B. The GPIO pins on each board allow the use of optional expansion boards.

Model A Model B
Target price:[1] US$25 (GBP £16) US$35 (GBP £22)
System-on-a-chip (SoC):[1] Broadcom BCM2835 (CPU + GPU + DSP + SDRAM)
CPU: 700 MHz ARM11 ARM1176JZF-S core
GPU: Broadcom VideoCore IV,[2] OpenGL ES 2.0, 1080p30 H.264 high-profile decode
Memory (SDRAM): 128 MiB 256 MiB
USB 2.0 ports: 1(provided by the BCM2835) 2 (via integrated USB hub)
Video outputs:[1] Composite video|Composite RCA, HDMI (not at the same time)
Audio outputs:[1] TRS connector|3.5 mm jack, HDMI
Audio inputs: none, but a USB mic or sound-card could be added
Onboard Storage: Secure Digital|SD / MMC / SDIO card slot
Onboard Network:[1] None 10/100 wired Ethernet RJ45
Low-level peripherals: General Purpose Input/Output (GPIO) pins, Serial Peripheral Interface Bus (SPI), I²C, I²S, Universal asynchronous receiver/transmitter (UART)[2]
Real-time clock:[1] None
Power ratings (provisional, from alpha board): 500mA, (2.5 Watt) [1] 700mA, (3.5 Watt)
Power source:[1] 5V via Micro USB or GPIO header
Size: 85.60mm x 53.98mm[3] (3.370 × 2.125 inch)


main article: Rpi Software

The Raspberry Pi is a fully capable ARM computer, so it should be able to run about everything compiled for ARM (within specifications) with little or no modification.

Accessories & Peripherals

Main article: RaspberryPiBoardVerifiedPeripherals


A protective case is an often-cited required accessory. Cases are likely to be offered both directly from Raspberry Pi and from 3rd party companies such as Special Computing. But given the small form factor and power requirements, you could easily put it in about everything: Rpi case thread

Power Adapters

Most power adaptors for modern cell phones will do (look for the microUSB connector)

  • Power supply Warning: Cheap-ass knock-offs usually cannot cope with the power demand of the Rpi, so watch out!


Main article: Rpi Screens

The Broadcom BCM2835 only provides HDMI output and composite output (the yellow plug on your tv). While the HDMI output is easily converted to DVI using a passive adaptor, it cannot be converted to VGA.

  • Even HDMI to DVI and then DVI to VGA won't work, as there is no analog signal needed for VGA.

Expansion boards

It is planned that expansion boards will be offered both by Raspberry Pi Foundation and by 3rd parties during 2012.

  • The first expansion board, nicknamed Gertboard after Gert van Loo, the developer of the Gerboard and one of the principal Hardware Engineers for Raspberry Pi, was announced on 17th December 2011: [1]
  • On 2nd January 2012, CJE/4D announced that they have a real-time clock (RTC) expansion board in the works: [2]


A manual is currently in production by members of the Computing At School working group. This began on the 13 October 2011 and is due to be ready for early March 2012. The manual is aimed at the project's target audience, children, so that they can take their "First steps in Computing Science".

For the first release (~January/February 2012), there will mostly likely be very minimal documentation. A 'schools' release is due in June/July 2012.

Display Output Options

The following display outputs are supported on the board:

  • Composite video (NTSC and PAL) via an RCA plug.
  • HDMI 1.3a standard output.
  • Display Serial Interface (DSI) - via unpopulated 15-way flat flex connector.

These interfaces allow the use of a broad range of displays, including:

  • Televisions (HDMI or composite).
  • Computer monitors (HDMI/DVI-D cable) (VGA monitors would require either a composite or HDMI to VGA scan converter box).
  • DLP/Laser Pico Projectors (HDMI/DVI-D cable).
  • RAW LCD panels (DSI + interfacing hardware)


  • The SOC does not support any kind of analog component video, including VGA, since the SOC is designed for mobile phone use where this would not be a requirement.
  • Composite and HDMI outputs can not be used at the same time (one or the other.)

Interfacing to Camera Module

is Sony sub-LVDS same as MIPI CSI-2? Sony IMX020 5Mbip module is available for $5-7 (SE K850i replacement camera).

Looks like Nokia N95 uses CSI-2 5Mpix camera module with autofocus. ~$15 replacement part.

General Purpose Input/Output (GPIO), I2C, I2S, SPI, UART

Production Board GPIO Header

The production board has a 26-pin 2.54mm expansion header, arranged in a 2x13 strip. They provide 8 GPIO pins plus access to I2C, SPI, UART), as well as +3V3, +5V and GND supply lines. Pin one is column 0 on the bottom row. All the UART, SPI and I2C pins can be reconfigured as GPIO pins, to provide a total of 17 GPIO pins.[4]

Voltage levels are 3v3. There is no over-voltage protection on the board - the intention is that people interested in serious interfacing will use an external board with buffers, level conversion and analog I/O rather than soldering directly onto the main board.

At least some of the GPIO pins support PWM.[5]

Each GPIO can interrupt, high/low/rise/fall/change.[6]

It is also possible to reconfigure some of the pins to provide an ARM JTAG interface.[7]

It is also possible to reconfigure some of the pins to provide an I2S or PCM interface.[8]

It is also possible to reconfigure some of the pins to provide a second I2C interface. [no-ref]

Kernel boot messages go to the UART at 115200bps.



Colour legend
Do not connect

Colour-coded Image: https://sites.google.com/site/burngatehouse/home/drawings/GPIOs.gif

Maximum permitted current draw from the 3v3 pin is 50mA. Maximum permitted current draw from the 5v pin is the USB input current (usually 1A) minus any current draw from the rest of the board, or about 650 mA. [9]

Driver support

The Foundation will not include a GPIO driver in the initial release, standard linux GPIO drivers should work with minimal modification.[10] The Foundation will not include a SPI driver in the initial release, we hope the community might write one.[11] The Foundation will not include an I2C driver in the initial release, we hope the community might provide one, standard linux I2C drivers should work with minimal modification.[12]


On the production board, we bring out the MIPI CSI-2 interface to pads for an unpopulated 15-way flat flex connector


On the production board, we bring out the DSI interface to pads for an unpopulated 15-way flat flex connector


HDMI-CEC is supported by hardware but some driver work will be needed and currently isn't exposed into Linux userland.

Eben notes that he has seen CEC demos on the Broadcom SoC they are using.

Software Details


The boards do not include NAND or NOR storage - everything is on the SD card, which has a FAT32 partition with GPU firmware and a kernel image, and an EXT2 partition with the rootfs.

We're not currently using a bootloader - we actually boot via the GPU, which contains a proprietary RISC core (wacky architecture ;) . The GPU mounts the SD card, loads GPU firmware and brings up display/video/3d, loads a kernel image, resets the SD card host and starts the ARM.

You could replace the kernel image with a bootloader image, and that would work fine.


Source code and binaries for Raspberry Pi will be available at various places from launch, including pre-built Linux distributions.

Ubuntu is currently listed as the default distribution on the Raspberry Pi website, but the Ubuntu developers have now stated they will not be supporting the ARMv6 architecture, so Ubuntu is likely to be dropped.

Eben says (regarding default distribution): "Either Ubuntu or Fedora; the main point in Fedora’s favour is their ongoing support for ARMv6 architectures."

Main page: RaspberryPiBoardDistributions

Development environments

Instead of just using compiler + editor, you can use "development tool chains" which integrate compiler, build system, packaging tools etc. in one tool chain.


The Broadcom processor on Raspberry Pi contains an ARM v6 general purpose processor and a Broadcom VideoCore IV GPU. No data is currently available on other cores (if any) available in the BCM2835.


There is broad compiler support including gcc - please see ARM Compilers

The ARM is capable of around 500 BOGOMIPS [13], 5400 LINPACK KFLOPS with software floating point and 22000 KFLOPS with softfp hardware floating point[14].


The GPU provides APIs for Open GL ES 2.0, hardware-accelerated OpenVG, and 1080p30 H.264 high-profile decode.

The GPU is capable of 1Gpixel/s, 1.5Gtexel/s or 24 GFLOPs of general purpose compute and features a bunch of texture filtering and DMA infrastructure - the Raspberry Pi team are looking at how they can make this available to application programmers.

The GPU blob is an 18MB as an elf file, plus libraries. It does an awful lot. [15]


There is a DSP, but there isn't currently a public API (Liz thinks the BC team are keen to make one available at some point).

Other software


From Eben: "We'll have to take a look. We support hardware-accelerated OpenVG, and have had Flash Lite running incredibly fast. Personally, I'd like to get the official hardware-accelerated Flash 10 going on there, running against OpenGL ES 2.0, but that's something to think about after the launch."

Software hints

This section collects hints, tips & tricks for various software components.


Performance Page


  • For Raspberry Pi frequently asked questions (FAQ) see FAQ.
  • Raspberry Pi Forum FAQ: Forum FAQ

News articles and blog posts about Raspberry Pi


Extension:RSS -- Error: "http://www.raspberrypi.org/wp-content/plugins/mingle-forum/feed.php?topic=70" is not in the whitelist of allowed feeds. There are no allowed feed URLs in the whitelist.




See also Schematic / Layout

Raspberry Pi wiki pages






Home page

raspberrypi.org (RaspberryPi home)

  • Using Google you can search raspberrypi.org (including Forum) using site:raspberrypi.org <search term>. The home page and forum each have their own search facilitiy also.

Manuals and resources

Contact and communication


Education & Training materials

Main page: RaspberryPiBoard/EducationalLinks


Raspberry Pi plans to support Python and C as primary teaching languages, but expect to have some sort of BASIC on there too. Perhaps even BBC BASIC or SuperBASIC depending on copyright issues.

Programming languages, IDEs, etc

Languages tested on Alpha board

  • Interp
  • Scala
  • Clojure
  • OCaml
  • gcc
  • g++
  • Python [16]
  • Perl
  • Ruby 1.9.2 (KidsRuby)

Expected to work

See also: RaspberryPiBoard/EducationalLinks for education-friendly languages.

Graphical Programming



See also Category:Education



Products are RoHS and CE compliant. Please contact Raspberry Pi for details regarding WEEE in your country.


Raspberry Pi will ship worldwide to the best of their ability (ie subject to UK export and local import laws).

Countries that may block the import due to their local laws include China (products imported or re-imported into China require a CCC certificate). This author is unaware if development boards such as the Raspberry Pi require a CCC certificate.

Countries that are currently subject to UK (including EU and UN) export restrictions include North Korea, Iran, Ivory Coast, Liberia and Zimbabwe. A full list and further details are provided at http://www.businesslink.gov.uk/bdotg/action/layer?topicId=1084100244

Raspberry Pi devices will ship from the UK (and possibly US) and Raspberry Pi will be looking to sign up distribution partners in due course.

To have an idea of shipping cost why don't you look at the Royal Mail website: http://sg.royalmail.com/portal/rm/PriceFinder?catId=23500532&gear=pricingcalc&campaignid=pricefinder_redirect

Look for a package just bigger then 85mm x 55mm x 30mm, weight about 55 grams.

As an example: New Zealand, small package 100grams, air mail 5 days : £2.05


  • The layout for this page is based on the excellent BeagleBoard page on this site.
  • Some of the text on this page has been adapted from contributions made by the contributors to the BeagleBoard page on this site.


Foreign Language Translations