STMicroelectronics STR91X-SK/KEI

Overview

STR91X-SK/KEI from STMicroelectronics is a Keil™-branded starter kit for STR91xF ARM966E-S core-based microcontrollers, including the STR912FAW4 device, featuring dual USARTs, SPI, I²C, CAN, USB, Ethernet, 8 user LEDs, and SD/MMC support. It integrates ULINK™ USB/JTAG in-circuit debugger/programmer and ships with µVision3 IDE and 16 KB-limited ARM RealView Compilation Tools.

For engineers reviewing the STR91X-SK/KEI datasheet, STR91X-SK/KEI pinout, STR91X-SK/KEI application, or STR91X-SK/KEI equivalent, this kit delivers validated hardware-software co-development capability for ARM9-based embedded control, industrial connectivity, and real-time communication prototyping - with full JTAG debug, on-board peripherals, and production-ready interface options.

Technical Context

The STR91X-SK/KEI implements a complete evaluation platform centered on the STR912FAW4 microcontroller (ARM966E-S core, 96 MHz, 256 KB Flash, 64 KB SRAM), paired with ULINK™ for seamless µVision3-hosted debugging. Its architecture supports real-time kernel integration via RTX and enables rapid firmware iteration through USB-powered operation and 20-pin JTAG access.

Hardware features include dual USART interfaces (RS-232 level-shifted), 2× CAN transceivers, 10/100 Mbps Ethernet PHY, micro-USB host/device port, QVGA LCD connector, SD/MMC slot, and 8-channel ADC with potentiometer input - all mapped to accessible headers and onboard peripherals for immediate functional validation.

Key Specifications

Availability

STR91X-SK/KEI is available at Aetrix Electronics and suitable for industrial connectivity gateways, ARM9-based protocol stack development, and real-time embedded control applications requiring stable component supply and full debug visibility.

Supply support for STR91X-SK/KEI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing microcontrollers, power management ICs, sensors, and analog devices for industrial, automotive, and consumer markets.

The STR91x family targets high-integrity industrial control and networking applications, emphasizing ARM9 performance, integrated CAN/Ethernet/USB, and robust real-time OS compatibility - optimized for deterministic communication stacks and field-deployable edge nodes.

FAQ

Does STR91X-SK/KEI support debugging without a separate JTAG probe?

Yes - it includes the ULINK™ in-circuit debugger/programmer with USB interface and 20-pin JTAG connector, fully integrated with Keil µVision3. No external debug hardware is required to download, run, or step-debug code on the STR912FAW4 target MCU.

What software tools are included with the STR91X-SK/KEI kit?

The kit ships with Keil µVision3 IDE, the 16 KB-limited version of ARM RealView Compilation Tools (C/C++ compiler), and RTX real-time kernel. All tools are pre-licensed for use with the STR91x target and require no additional activation for evaluation.

Can the STR91X-SK/KEI be used for CAN FD or USB OTG development?

No - the STR912FAW4 MCU supports only classical CAN 2.0B (not CAN FD) and USB 2.0 Full-Speed device/host (not OTG). The board provides two standard CAN transceivers and a single micro-USB port wired for device/host mode per ST's reference design.

Is external power required to operate the STR91X-SK/KEI?

No - the board is fully USB-powered and operates from the host PC's USB port. An optional 7–12 V DC external supply may be used via the barrel jack for higher-current peripheral testing or when USB power is unavailable.