| p>INTRODUCTION: TI OMAP 3430 microcontroller is a | | | | Managing all that functionality and the high resolution |
| highly integrated controller directed at the Smartphones | | | | video needs a truly innovative processor core. It is |
| segment. It supports most functions needed of a | | | | worth investigating how the ARM Cortex-A8 |
| Smartphone controller in practically just one chip | | | | implements the functionality. |
| package. All you need are some support chips | | | | THE CORTEX-A8 CORE: The Cortex family is based |
| surrounding it, to make a Smartphone product. Beside | | | | on the latest ARMv7 architecture from ARM. There |
| the main phone functions and email + IM functions that | | | | are three flavors of the processors from this family; |
| are considered necessary today; handling video is the | | | | applications processors, real time processors and |
| biggest challenge for such processors. Video, | | | | microcontrollers. |
| particularly HD video takes a lot of processor power. In | | | | The applications processors support a full fledged |
| a mobile application keeping the power budget low is | | | | virtual memory complexity and use a MMU. The real |
| another necessity. Looks like the TI OMAP 3430 does | | | | time processors are expected to be used for deep |
| that well. It is the first member of the OMAP 3 family | | | | embedded use and only a memory protection unit is |
| aimed at the Smartphone segment. | | | | provided. The micro-controllers version does not have |
| Palm Pre uses the processor as does some models | | | | either a MMU or a MPU and only straight addressing |
| of Sony Ericsson. Apple is rumored to be considering | | | | space is supported. |
| this processor for a future upgrade. It is interesting to | | | | The cortex-A8 is capable of processing VGA, H.264 |
| take a look at how Texas Instruments is managing this | | | | video at 350 MHz and does it at a low power budget |
| difficult trade off; the trade off between high loads of | | | | of 300 mW! The main features that make the |
| processing within a low power budget! | | | | processor fast are a superscalar architecture, a deep |
| THE OMAP 3430: The key to the solution is the | | | | multi-stage instruction pipeline and a video processing |
| choice of using the newest ARM Cortex-A8 | | | | engine based on what they call NEON technology. |
| processor core as the workhorse in this solution. This | | | | They have also implemented the Thumb-2 technology |
| is supported by two major blocks that help with all the | | | | that produces very dense code. Code that take up |
| graphics and multimedia workload. One is a 2D/3D | | | | low memory space yet is powerful enough to |
| graphics accelerator and the second one is a imaging | | | | implement meaningful functionality. Thumb-2 is |
| video accelerator. Other blocks implemented in the TI | | | | supported by runtime Jazelle RCT that produces just |
| silicon solution include LCD interface, Camera interface, | | | | in time byte-code. |
| a USB OTG port, memory control and DMA control, | | | | The superscalar arrangement issues two instructions |
| various interconnects and peripheral support and a | | | | for parallel execution by the two execution units |
| video out port. | | | | available. This is a in-order pipeline. Out of order pipeline |
| Some of the functions supported are GPS | | | | would have called for addition of complex logic on chip. |
| functionality, mobile TV interface, wireless link, mobile | | | | So that was traded off against the need for keeping |
| data and voice interface, a modem interface and a | | | | power consumption low. So you have the potential to |
| touch screen controller. One supporting chip TWL | | | | double the performance most of the time. |
| 5030 not only manages power but supplies audio | | | | A 13 stage instruction pipeline you have the instructions |
| video codec support. It also manages USB and | | | | working 13 times faster in a strict sequential program. |
| keypad interfaces. Other interfaces provided are Flash | | | | On an average one could expect at a least order |
| memory interface (NAND or NOR), a mobile DDR | | | | more of processing speed. Combine all that with a |
| interface, Trace and JTAG interfaces. Some GPIO | | | | separate SIMD video processor with its own pipeline |
| lines, a camera serial/parallel and a serial camera | | | | and you start to see why the Coretex-A8 is such a |
| interface are also available. Lastly, a group of | | | | powerful device. Add the embellishments TI has and |
| interfaces provide a flash memory card interface, a | | | | you have a very powerful engine for implementing |
| TV interface with S-Video and a display controller | | | | Smartphones. |
| Parallel-serial. | | | | |