AndesCore™ D15/D15F Overview

  • Dual-issue pipeline
  • > 130 DSP extension instructions
  • Caches for fast code and data accesses
  • Local Memories for deterministic code and data accesses
  • Built-in IEEE754-compliant FPU coprocessor (D15F)
  • Memory Management Unit (MMU) for Linux
  • 64-bit AXI4/AHB/AHBx2 bus interface

D15/D15F are the first dual-issue superscalar AndesCore™ processors. Both processors feature over 130 compiler friendly, general purpose DSP and SIMD instructions that enable easy DSP algorithm programming in C/C++. D15/D15F comes with a variety of configuration options, including MMU, cache and local memory. The 64-bit data buses for caches, local memory and the main bus provide the bandwidth needed for instruction fetch and data access. D15F includes a built-in IEEE-754 compliant floating point unit that enhances the floating point processing capability. D15/D15F is designed for diversified performance-driven applications on the embedded Linux, Real-Time OS or bare metal environment.
 

Applications

  • Biometric devices
  • Wireless modem
  • Voice/speech recognition
  • Global Position System (GPS)
  • Unmanned Aerial Vehicle (UAV)
  • Sensor device/Sensor hub
  • Advanced motor control

Block Diagram

Development Tools

  • AndeSight™ Integrated Development Environment
  • AICE JTAG/SDP debugger hardware

Key Features and Performance

AndeStar™ V3 Architecture
Key Features Benefits
21st-century RISC-like instruction set Better performance for modern compiler
16/32-bit mixable opcode format Smaller code size
32 general-purpose registers Trade-off between core size and performance requirements
All-C Embedded Programming Faster SW development and easier maintenance
Shadow stack pointer Efficiency and protection with a dedicated kernel stack pointer
Radix-4 hardware divider More performance
Aligned and unaligned load/store multiple word instructions and post-increment load/store memory accesses Better program code size and performance
64-bit load/store unit More performance
Direct support of up to 32 interrupts with programmable priority levels Quick identification of interrupt sources and fast assignment of service routines
4G address space Full range address space
Memory mapped IO Easy to program and friendly to compiler
CPU Core
Key Features Benefits
3.36 DMIPS/MHz* 5.41 CoreMark/MHz* Superior performance-per-MHz
6-stage dual-issue pipeline Capable of processing two instructions in parallel to accelerate performance
DSP extension instructions
  • > 130 instructions
  • Zero-overhead loop
  • Saturation and Rounding
  • Fractional Q31/Q15/ Q7 data types
  • Integer U32/U16/ U8 data types
  • 16-bit and 8-bit SIMD instructions
  • 64-bit signed/unsigned addition & subtraction
  • GCC intrinsic functions to use in C
  • GCC vector data type for SIMD instructions
Digital signal processing performance enhancement
  • 2X performance for Helix MP3 decoder
  • 2X performance for G.729AB codec
 
Extensive branch predication (BTB and RAS) Better performance for branches
Hardware stack protection Stack size determination and runtime overflow error detection
Processor state bus Simplification SoC design and debugging
Performance monitors Program code performance tuning
Memory Management Unit
  • 32/64/128-entry 4-way set-associative main TLB
  • Hardware page table walker
  • Support two groups of page size (4KB & 1MB, 8KB & 1MB)
  • Virtual memory support for full address space and easy code/data sharing
  • Support for full-featured OS such as Linux
  • Protection of superuser and user privilege
  • Hardware for fast address translation
Memory Protection Unit
  • 8 memory protection regions
Basic read/write/execute memory protection with minimum cost
 
Fast multipliers (1 cycle) More performance
Extensive clock gating and logic gating Lower power
N:1 core/bus clock ratios Simplified SoC integration
Low-latency vectored interrupt Faster context switch for real-time applications
Completion of most operations in 1 cycle Single-cycle capable for Local Memory and AHB bus accesses Better performance-efficiency
PowerBrake technology Peak power consumption reduction
QuickNap™ automatic state management for fast power-off and wakeup Better power management efficiency
Floating point unit (D15F)
  • IEEE 754-2008 Compliant
  • Single precision (SP) or Double precision (DP)
  • 32 registers for SP, 16 or 32 registers for DP
  • Support all rounding modes and exceptions
  • Support Flush-To-Zero mode to speedup denormalized number processing
  • Arithmetic  (+, -, x, ÷, √ ), Fused MAC operations
  • Compare and format conversion instructions
  • Copy/Move, Load/Store instructions
For floating point application

* Toolchain BSP v 4.2.0

Memory Subsystems
Key Features Benefits
I & D Cache
  • Virtually Indexed and Physically Tagged (VIPT)
  • Size:4KB to 64KB, line size:32B
  • Set associativity: 2-way (I-Cache), 4-way (D-Cache)
Higher performance for large program size
  • Accelerating accesses to slow memories
  • Flexible cache configurations
  • VIPT for low power on context switch
Optional External Instruction and Data Local Memory
  • Size: 1KB to 16MB
  • 64-bit ILM: program code, data and IO
  • Dual 32-bit DLM: program data
Higher efficiency for program execution
  • Flexible size selection to fit diversified needs
ECC or Parity for soft-error protection (Parity protection is valid for D-cache and DLM only) Code and data integrity protection
Optional 1D/2D DMA with 64-bit transfer Efficient data transfer
BIU supports 64-bit AXI4/AHB/AHB2  User-selectable bus interface for optimal efficiency
Debug Support
Key Features Benefits
5-wire JTAG Debug Port/Andes 2-wire Debug Port   Industry-standard 5-wire support and Low-cost 2 wire support 
Embedded Debug Module (EDM)
  • Up to 8 breakpoints and watchpoints
  • Secured debug access to system address space
  • Flexible configurations to trade off gate count and debugging capabilities
  • Code and data protection by allowing only authorized debugging
Trace interface to the Andes Trace Module (licensed separately) for enabling the tracing capability
  • Advanced debugging
Performance
Process 28HPM
Frequency (MHz) 50
Dynamic power (uW/MHz) 18.0
Area (mm2) 0.054

* Base configuration, RVt library. Frequency at slow process corner, 0.9Vdd, 125°C; Power consumption at typical process corner, Vdd, 25°C

Process 28HPM
Max frequency (MHz) 830
Dynamic power (uW/MHz) 12.0
Area (mm2) 0.107

* Base configuration, LVt library; Frequency at slow process corner, 0.9Vdd, 125°C and without I/O constraint;
  Power consumption at typical process corner, Vdd, 25°C