【C-SKY Embedded CPU —— 8-Bit CPU Cost, 32-Bit CPU Efficiency】

CK802 is a low cost and low power embedded CPU core. It offers 32-bit performance at the cost of 8-bit CPU. Based on C-SKY V2 instruction set architecture and 16/32-bit variable length instruction system, CK802 achieves benefits as extremely low cost, low power and high code density. CK802 family includes basic core (CK802), JAVA acceleration (CK802J), physical attack defensing extension (CK802S), and trusted execution extension (CK802T).

Main technical features of CK802

· Reduced instruction set architecture, 32-bit data, 16/32-bit variable length instructions;

· 0.93 DMIPS/MHz

· 2-stage low cost pipeline, single issue in-order execution;

· Static branch prediction;

· One-cycle execution delay of most instructions and data forwarding technology;

· Multi-mode dynamic power management;

· 13 cycles interrupt latency from interrupt asserting to interrupt handler processing;

· Memory access protection, 0~8 memory protection regions;

· Tightly-coupled system IP, including vector interrupt controller, timer and power management unit;

· Physical attack protection technology designed to prevent time analysis attack, power analysis attack, fault injection and stack overflow attack;

· Trusted execution technology against software attack;

· JAVA Accelerator technology for JAVA execution acceleration;

· Program signature technology to prevent malicious tampering;

· Power control technology to control average power and peak power;

· Configurable cache;

· Configurable hardware debugger supporting on-chip hardware debugging;

Application fields of CK802

· Smart card applications;

· Intelligent metering products;

· Low-cost microcontrollers;

· Wireless sensor networks, etc.

Structural and design features of CK802

CK802 implements performance- and power-optimized micro architecture. The minimum core area of CK802 is 12,000 gates. CK802 realizes an extremely simplified 2-stage pipeline including fetch and execute. Fetch stage implements a low-cost static branch predictor to achieve prediction accuracy up to 80%. Execute stage takes responsible for decoding, execution and written back. The vast majority of instructions can be executed and written back within one cycle. CK802 provides advanced dynamic power management technology which provides different low power modes and controls the peak power and average power of CK802.

CK802 supports configurable on-chip cache (capacity of 2/4/8KB) and realizes one-cycle data access. It improves system operating efficiency and performance greatly by effectively filtering processor’s access to off-chip memory.

Security protection technology

CK802 provides comprehensive, multi-level security protection technologies, including physical attack prevention technology, program signature technology against program tempering, and trusted execution technology against software attack. The physical attack prevention technology offers 19 defense methods and is designed to effectively prevent time analysis attack, power analysis attack, fault injection attack and buffer overflow attack.

Trusted execution technology for IOT security

For IOT security, CK802 has developed the trusted execution technology based on virtualized trusted world and non-trusted world, which protects secure data in trusted world, and offers multiple layers of trusted protection features including trusted interrupt response and trusted debugging.