STR910F microcontroller series, rich in connectivity with Ethernet, USB and CAN interfaces plus generous on-chip SRAM and Flash memory, has received a performance make-over. The enhanced memory accelerator in the new STR910FA boosts performance by allowing the burst Flash memory to stream instructions more freely to its ARM966E CPU core. Peak performance remains the same, at an impressive 96 Million Instructions Per Second (MIPS) during the execution of sequential instructions, but the average performance has increased significantly when instructions are non-sequential, as a result of the larger memory accelerator.
An excellent measure of average performance is the AutoBenchTM test suite from Embedded Microprocessor Benchmark Consortium (EEMBC®), which consists of 16 real-time benchmark kernels. Real-world applications, such as those found in factory automation, building automation and security, and point-of-sale equipment are represented with tests that include bit manipulation, interrupt response, math and DSP function, CPU efficiency, and data movement.
AutobenchTM test scores for the STR910FA registered an average of 25% better than those of the STR910F, indicating improved overall system performance due to improved flow of instructions to the CPU. Additionally, the STR910FA showed an average performance gain of 36% over the closest competing Flash ARM7-based MCUs for like AutobenchTM tests. All tests are performed and certified independently by the EEMBC consortium, with results posted at www.eembc.org.
“Processor suppliers frequently claim performance improvements for their devices, but it’s less common to go the extra mile, as STMicroelectronics has done, and actually back up these claims with objective benchmark data,” said Markus Levy, EEMBC president. “The objective comparison between the STR910FA and STR910F devices enabled by EEMBC benchmark scores will give STMicroelectronics customers the solid information they need to evaluate the new STR910FA device and understand the potential benefits it can bring to their designs.”
In addition to improving performance, pricing for STR910FA devices has been reduced relative to equivalent STR910F devices, with resale prices for the new series starting at US$4.98 (STR910FAM32X6 in quantities of 10,000). This places powerful Flash ARM9-based MCUs in the same price range as similar Flash ARM7-based MCUs.
Six additional members of the series have been added to the family, offering more memory size combinations, plus tiny new BGA144 packages measuring only 10 x 10mm.
The STR910FA MCU series offer Flash memory up to 544Kbytes and SRAM to 96Kbytes with a full set of peripherals that include an Ethernet MAC, USB, CAN, three UARTs/IrDAs, two SPIs, two I2Cs, eight channel 10-bit ADC at 0.7 microsecond conversion, four 16-bit timers, a 3-phase AC motor-control unit, complete supervisor functions with Low Voltage Reset and Brown-out Detect, a full-featured real-time clock at just 1 microamps, an external memory interface, an ETM9 debug and trace interface, and up to 80 5V tolerant I/O. All devices operate between -40 to +85 degrees C.