# Big Picture

*(circa Q1 2012)*

The generic term "System on a Chip" refers to the fact that the CPU and many
"peripherals" (USB, ethernet, memory controller, GPU) are integraded into a
single package instead of being distributed across a motherboard via a
northbridge and southbridge. There still needs to be external analog and
digital circuitry for most "connectivity" interfaces like USB or ethernet to
provide level conversion, isolation, etc. Notably, RAM is not usually
integraded into the chip, and the large parallel bus to the RAM chips must be
routed very carefully. Some newer chips (popular circa 2010?) include "package
on package" technology where the RAM chip is right on top of the SoC to make
routing easier (eg, iPhones, RaspberryPI).

The establishment players for mobile ARM SoCs are TI (OMAP), Qualcomm
([Snapdragon](http://en.wikipedia.org/wiki/Snapdragon_(System_on_Chip))), not
regular ARM), Samsung ([Exynos](http://en.wikipedia.org/wiki/Exynos))), Broadcom (Armada, Armada XP, )

The establishment players for MIPS SoCs are Broadcom and Marvell (Kirkwood).

# ARM

### TI OMAP

[OMAP5 overview](http://www.linuxfordevices.com/c/a/News/TI-OMAP5430-and-OMAP5432-CES-demos/)

### Marvell Armada XP

[Marvell MV78200](http://www.marvell.com/embedded-processors/discovery-innovation/applications.jsp)

 - 4 GigE ports
 - 2x 1GHz armv5 chips
 - 2x SATA
 - 2x PCIe x4
 - $60 or less?

Samples available from 
[nu horizons](http://www.nuhorizons.com/featuredproducts/portal/samples/January_2012.asp)

Apple experimenting with these chip? [arstechnica article](http://arstechnica.com/apple/news/2011/09/support-for-quad-core-arm-cpu-shows-up-in-apples-xcode-but-why.ars)

### Calxeda "EnergyCore"

Going for massively parallelized market, with hundreds of cors in a rack. 

ECX-1000 is 4 Cortex-A9 at 1.1-1.4ghz, 5watts with 4gb DDR3 RAM. SATA and PCIe,
72bitwidth DDR3 controller (32bit addressing), up to 5 10GigE ports with
"routing fabric". Hard FPU.


### Freescale i.MX6

<http://en.wikipedia.org/wiki/I.MX#i.MX6x_series>

40nm process. 1.2GHz Cortex A9, up to 4 cores, includes vidoe processing
"stuff". Single PCIe, GigE, SATA, 64bit RAM bus, **$10-20** price range,
available summer 2012? Sabre Lite DevKits available to some?  

[linaro link with specs](https://wiki.linaro.org/Boards/MX6QSabreLite)

### Allwinner A10

A Chinese-made fast cheap (**"$5 in volume"**) tablet-oriented processor

 - <http://elinux.org/Hack_A10_devices>
 - <http://rhombus-tech.net/allwinner_a10/>
 - <http://www.wits-tech.com/pages/board.jsp>
 - SDK and tools docs <http://www.cnx-software.com/2011/12/28/allwinner-a10a1x-processor-resources-development-board-and-sdk/>

# x86

### Intel Atom

Line of devices with low-gate-count integrated Altera FPGAs. Great
connectivity, but higher price (**~$60?**), proprietary toolchain, higher power
consumption. 

# MIPS

Ingenic jz4760B

# PowerPC

AppliedMicro APM86290

# Other

Marvell Avanta ethernet switch SoCs: http://www.marvell.com/broadband/

Marvell Prestera EX/MX enterprise packet processors

Freescale QorIQ DPAA