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32-bit MCUs with on-chip SRAM

Renesas Technology Europe announced the release of a total of eight versions of the SH7266 and SH7267, two new high-performance 32-bit MCU products with an on-chip SRAM size of 1.5 MB, that are intended for embedded applications in the industrial and consumer fields such as displays for digital audio players or graphical dashboards. The SH7266 and SH7267 are the enhanced products of the SH7260 Series that belongs to the SuperHTM*1 Family of high-performance 32-bit RISC MCUs. They each have 1.5 MB of large-capacity on-chip SRAM, an increase of 50% from the 1 MB of earlier MCUs in the SH7260 Series, to take the place of external synchronous DRAM (SDRAM). This makes it possible to implement a VGA display (640 480 pixels) without the need for external SDRAM. The large-capacity SRAM can be used as a display frame buffer or as a work area for storing programs or data. The SH7266 is available in a 144-pin QFP package and the SH7267 in a 176-pin QFP package.

The SH7266 and SH7267 each have 1.5 MB of large-capacity on-chip SRAM that can be used in place of external SDRAM as a program or work area. The large-capacity SRAM can also be used as a display frame buffer for video data, eliminating the need to use external SDRAM for the frame buffer. When used as a frame buffer, the large-capacity SRAM can store two frames of video data in VGA format, an increase from the WQVGA format (480 240 pixels) of earlier products in the same series, which can be displayed on a TFT LCD panel via a display controller. This contributes to reducing overall system cost and size.
The SH7266 and SH7267 provide a new video display controller and digital video input pins for use with graphical and video display applications. These support functionality such as video recording, size reduction, alpha blending effects (superimposition of transparent or semitransparent images), and superimposition of video input. Digital RGB output pins allow output of images or video in RGB565 format (in which each colour is represented by 16 bits: 5 bits for the red [R] component, 6 bits for green [G], and 5 bits for blue [B]) at up to VGA size.

This on-chip functionality makes it possible to develop products, such as car information systems with rear-view or side-view camera display and midrange or low-end graphical dashboard systems, using fewer devices and at a lower cost.
The SH7266 and SH7267 each have a large number of on-chip peripheral functions, including Hi-Speed USB 2.0 (host and function modes). In addition to standard serial interfaces such as serial communication interfaces with 16-stage FIFO and I2C bus interfaces, the SH7266 and SH7267 are equipped with serial sound interfaces for digital audio data I/O, a CAN*2 interface, 16-bit timers including CMT and MTU2, and PWM timers for motor control. This array of on-chip peripheral functions provides support for a wide range of applications. Also integrated on-chip is a 16-bit external bus controller that enables direct connection to flash ROM, SDRAM, or SRAM without the need for additional external components.

The SH7266 and SH7267 are built around the SH2A-FPU CPU core (which incorporates an FPU), have a maximum operating frequency of 144 MHz, and deliver excellent processing performance. The instruction set of the SH2A-FPU is backward compatible with the SH-2A and SH-2 CPU cores, allowing developers to reuse program code created for earlier products. In addition, ROM code efficiency has been improved approximately 75% in comparison with the SH-2. As a result, the object code for the same program can be compressed to about three-quarters the previous size, conserving the memory capacity available for storing programs.

In addition to the above, the peripheral functions have been supplemented as follows.
In addition to NOR flash memory, the SH7266 and SH7267 allow connection of other external flash memory types such as NAND flash memory and serial flash memory. The device can be booted from a program read in from the external flash memory. These microcontrollers are thus excellent solutions for systems employing many different types of flash memory.

Hi-Speed USB2.0 (host and function modes) is implemented on-chip. When host mode is selected, the device can connect to and communicate with multiple peripheral devices via a hub. Switching between the host and function modes is easily accomplished by register settings. The USB has a built-in USB transceiver that supports all data transfer types defined in the USB standard.

A CD-ROM decoder and a sampling rate converter for converting the sampling frequency for audio data are implemented on-chip. These functions are required by digital audio devices. Other on-chip peripheral functions suitable for a variety of applications include a Renesas SPDIF interface, a direct memory access controller, and a SD memory card interface.

These many on-chip peripheral functions enable developers to build systems delivering advanced functionality with a smaller number of total components. This contributes to reduced overall system cost.

The SH7266 and SH7267 are each available in four product versions with different combinations of CAN interface and IEBus*3 interface availability, for a total of eight product versions. Additionally, each product version is available with an operating temperature range of either -40 to 85C or -20 to 85C, resulting in a total lineup of 16 product numbers. Customers can select the product version that best meets their requirements.

The SH7266 comes in a lead-free 144-pin QFP package and the SH7267 in a lead-free 176-pin QFP package. Both have an on-chip debugging function*4 that enables real-time debugging at the maximum operating frequency. The E10A-USB emulator, which uses USB bus power and requires no external power supply, is available as a development environment.

Renesas Technology supplies middleware with support for digital audio compression standards such as MP3, WMA (Windows Media Audio)*5, and AAC (Advanced Audio Coding). In addition, software is available that provides support for the ISO 9660 file system used by CD-ROM drives, the FAT32 file system used by hard disk drives, USB mass storage class drivers, and others. The available software libraries support devices requiring storage and communication capabilities, such as USB functionality for digital audio devices or embedded applications.