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Atmel Introduces Industry's First ARM Cortex-M3 Flash MCU With On-Chip High Speed USB Device-and-Transceiver
Atmel announced the SAM3U, the industry's first ARM Cortex-M3 Flash microcontroller integrating high speed (480 Mbps) USB Device-and-Transceiver, 4-bit 192 Mbps SDIO/SDCard 2.0, 8-bit 384 Mbps MMC 4.3 Host and 48 Mpbs SPI interfaces on-chip. This connectivity, together with the SAM3U's 96 MHz/1.25 DMIPS/MHz operating frequency, makes the SAM3U Cortex-M3 device suited to applications with intensive communications requirements, such as high speed gateways in industrial, medical, data processing and consumer applications.
It features 23 DMA channels and distributed on-chip memory including up to 52k Bytes of SRAM split in three blocks and up to 256k Bytes of Flash in two banks. The dual bank Flash offers in-application programming (IAP) where one memory bank is written with a new version of the firmware while the processor executes from the other bank. A programmable boot feature enables switching between the two Flash banks at the next MCU reboot.
Additional features include an 8-channel each 10- and 12-bit ADC, the latter with integrated Programmable Gain Amplifier (PGA), differential and single ended input to remove external OpAmps and a one Msps sample rate, 4 UARTs, 5 SPI, 2 I2C, I2S, timers, PWM, 128-bit unique ID, and power and reset management. The External Bus Interface offers the choice between 8- and 16-bit data bus widths for extended memory or connection to external FPGAs and ASSPs. The SAM3U's supply voltage ranges from 1.62V to 3.6V, a feature not commonly found on Cortex-M3-based MCUs.
Power optimization - The SAM3U incorporates a sophisticated power management regime that minimizes power consumption under all conditions of use. The device can be put in Backup mode with the core and peripherals powered down, in which power consumption is only 2.5 uA. Wake-up from backup mode can be triggered by multiple sources and is accelerated via a high speed on-chip RC Oscillator reducing the average power consumption critical for battery operated systems.
Code portability between SAM7 and SAM3 MCUs - The Cortex-M3 core has a completely new instruction set architecture, different from previous ARM cores. Migrating legacy ARM7 code to the Cortex-M3 requires a complete re-write of the assembler code. Atmel has taken steps to ensure maximum code portability between its ARM7-, ARM9- and Cortex-M3-based microcontrollers. Its SAM7, SAM9 and Cortex-M3-based SAM3 MCUs have identical hardware abstraction layers and a unified programming model, as well as common peripherals that provide near-recompile-and-go code portability between devices.
Comprehensive support eco-system - Atmel's SAM3U flash MCU is supported by a rapidly growing number of development tools, real-time operating systems (RTOS), middleware products and technical support services from industry-leading third parties that include IAR(R), Keil(R), Micrium(R), and Segger(R). Atmel provides a software package with register descriptions and device drivers for all peripherals, along with project examples that ease the use of the microcontroller. The SAM3U Evaluation Kit is available for benchmarking and a quick start in application development.
Availability and Pricing - The AT91SAM3U is available in Flash memory densities of 64k, 128k and 256k Bytes and ships in 100 and 144 pin 0.5mm pitch QFP and 0.8 mm pitch BGA packages. Samples are available now. Production volumes will be available in 4Q09, with prices starting at US$3.50 in quantities of 10k units. |  | | | The block diagram of the SAM3U
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Comments: Atmel is very late with the SAM3 or the SAM3U and the big feature is really the USB2.0 HS. Nevertheless, many applications that are using the high speed USB will also use much more memory than that available on the SAM3U, so there is little incentive not to go with an ARM9 to begin with. The external bus interface is rather limited and will be sluggish, no SDRAM or DDR-RAM support. Why would an application use an interface that enables transmissions of 480 Mbit/sec to fill the whole SRAM on the chip within approximately 1 ms. This chip could probably make a very fast memory card reader with USB and SD/MMC interfaces but for that it could be a little bit expensive. The 17-in-one card readers sell right now for about $5. Atmel has good name recognition in the ARM7 / Cortex-M3 market that will help to place the SAM3U. Facing an uphill battle in-house against AVR32 and being late in the game will not make it easy. The pricing of $3.50 for a 64k MCU with USB2.0 HS can only be justified for customers needing the USB 2.0 HS. For those customers though that need USB2.0 HS, want a Cortex-M3 based MCU, do not need any significant memory, the AT91SAM3U is unique. An interesting feature is the low voltage operation down to 1.62 Volt, it enables low power operation as well as long battery life. Keep in mind that analog parts on the MCU will need a higher voltage to operate, the ADCs have a min analog supply voltage of 2.4V. Planned derivatives include the 100-pin devices SAM3U1E, SAM3U2E, SAM3U4E as well as the 144-pin devices SAM3U1C, SAM3U2C, SAM3U4C A summary sheet for the ATSAM3U Series is here for download (1.4 MB 57 pages) The reference manual, complete datasheet, users manual or programmers manual for the ATSAM3U Series, however you want to call is here (21.6MB 1120 pages) More about Cortex-M3 devices that have been recently announced and compete with the SAM3U Training for Cortex-M3 including CMSIS software standard through Doulos |
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