Because they contain an extensive array of hardware functions and more internal memory, the new MCUs make it possible to design with a single-chip mid-range and low-end consumer, automotive and industrial products that provide economical graphics capabilities or TV display functions. Depending on a model, the MCUs have 18 to 20 peripheral functions that are sufficient for handling the many timing, communication, decompression, data conversion, and other tasks required in such applications. (Typically, the only additional IC needed is a read-only ROM chip for storing programs.)
The new MCUs are members of the SuperH family. They incorporate an SH2A-FPU CPU core with floating point unit (FPU) hardware that attains high code efficiency and runs application code quickly. Processing performance is excellent: 346 MIPS (Dhrystone 1.1 benchmark) and 288 MFLOPS at 144MHz. This high level of throughput enables the devices to perform embedded control tasks and multimedia processing, while also communicating with external devices. Further, the combination of excellent signal-processing performance and high ROM code efficiency they offer facilitates compression and decompression of audio data in formats such as MP3, WMA, or AAC (Advanced Audio Coding) more rapidly, while reducing program sizes.
Both the SH7262 and SH7264 series contain eight models—versions differentiated by temperature range (-20 to +85°C or -40 to +85°C) and whether or not they have CAN or IEBus interfaces. The SH7262 series MCUs are packaged in a 176-pin QFP and have four channels of A/D converter, while the SH7264 series devices come in a 208-pin QFP and have eight A/D converter channels. The QFP packages are lead-free types.
Industry top-class SRAM capacity
The 1Mbyte of SRAM built into the SH7262 and SH7264 MCUs can be configured as a frame buffer for temporary storage of video data for graphical displays. With these MCUs, it’s possible to drive a WQVGA-size TFT LCD panel (480 × 240 pixels) without external SDRAM for video memory. Larger displays up to VGA can be driven by the SH7262 and SH7264 if external SDRAM is used for the frame buffer, and the on-chip SRAM can be used to store either programs or other types of data.
New graphical display functions
Among the MCUs’ numerous on-chip functions are a new video display controller and digital video input pins that are useful for graphical and video display applications such as rear-view or side-view cameras. These peripherals support video recording, image-size reduction, alpha-blending effects (superimposition of transparent or semitransparent images), and superimposition of video inputs. Digital RGB output pins allow images or video to be displayed on WQVGA screens in the 16-bit RGB565 format.
Other on-chip functions in the MCUs’ extensive sets of peripherals include a motor-control pulse width modulation (PWM) timer that can control the display of up to four gauges, an SD memory-card interface, a hardware circuit for decompressing graphical data, a USB 2.0 Hi-Speed specification host/function interface, an audio signal processor, and a CD-ROM decoder. Additionally, there is a 16-bit external data bus that supports direct connection to external memory such as flash ROM, SDRAM, or SRAM without external parts.
Typical applications
In products such as digital car audio systems and home audio equipment, the MCUs in the SH7262 and SH7264 series can implement the ability to dock portable audio players and display video from players that have video playback functions. In automobiles, the devices can be used to drive a color LCD instrument panel that shows not only the speedometer and tachometer, but also readouts of fuel level, coolant temperature, oil pressure and other information, plus warning indications, camera images, and navigation data. Additionally, the new series will be ideal for accessories for standalone or built-in media players such as alarm clocks and external speakers as well as products that require MMI employing audio and graphics.
For system development, the MCUs have an on-chip debugging function that
allows system engineers to perform real-time debugging at the devices’
full 144MHz operating frequency. The E10A-USB emulator, which uses USB
bus power and thus requires no external power supply, is available as a
development environment. Renesas Technology supplies middleware
supporting digital audio compression standards such as MP3, WMA, and
AAC. The MCUs can implement designs with multi-codec compatibility.
There is also software available that supports the ISO 9660 file system
used by CD-ROMs and the FAT32 file system used by hard disk drives.
Renesas is developing a platform solution with a reference board and
middleware, including codecs for audio, GUI libraries and development
tools and real-time operating system support from Renesas ’
partner companies.
