Microcontrollers Handle Automatic Speech Recognition
Spansion adds a pair of HyperBus capable microcontrollers to their collection. The two new FM4 systems are based on the ARM Cortex-M4. One includes a 2D graphics engine with on-board VRAM while the other includes voice recognition software and hardware support. The graphics family includes support for Spansion's HyperBus, a fast, off-chip memory access system (see “How HyperBus Delivers 330 Mbyte/s Using A Dozen Signals”). Both families support QSPI and SPI memories and peripherals.
The 160 MHz S6E2DH series (Fig. 1) has the 2D graphics engine with 384 Kbytes of flash and 36 Kbytes of RAM. The 2D engine can handle functions like image scaling, alpha blending, anti-aliasing, pan/zoom/rotation and on-the-fly image compression. It can handle displays with SVGA, 800 by 600 pixel resolution and 4- to 24-bit pixels. The 2D controller has its own 512 Kbytes of RAM.
The S6E2DH series targets low cost, human-machine interface (HMI) applications. The on-board VRAM reduces the bill-of-materials (BOM) while providing high performance graphic support.
The 200 MHz S6E2CCA series (Fig. 2) foregoes the 2D graphics engine and bulks up on memory to provide automatic speech recognition (ASR) support. It has a dual bank of 1 Mbyte flash along with 256 Kbytes of RAM.
The ASR support can handle over 100 commands in real time. It is speaker independent so it does not require training. Commands can be defined using a text file and there is support for multiple languages. The system is designed to check for voice activity and recognize a wake-up keyword.
Product-specific development boards are available.