1. FPGA Microprocessor
Cores
company

2. Hardcore
• PowerPC
Softcore
• PicoBlaze
• MicroBlaze

3. PowerPC
PowerPC 405 features
 Embedded32-bit RISC processor with

•


Harvard architecture
5-stage pipeline (fetch, decode, execute, write
back and load write back stage)
Branch prediction
Hardware multiply/divide unit
The auxiliary processor unit (APU)

4. PowerPC 405 functional unit
 Instruction and data cache, 16 KB each
 Memory management unit with 64-entry
translation lookaside buffer (TLB)
 Fetch & decode unit
 Execution unit with thirty two 32-bit generalpurpose registers, ALU , and MAC (Multiple
Accumulate Unit)
• Timers
 Debug logic

5. PPC405 Organization

6. PicoBlaze:
PicoBlaze key features
 Embedded 8-bit RISC processor
 16-byte-wide general-purpose data registers
 256-1024 instruction words
 Byte-wide ALU operation with carry and zero




flags
64-byte internal scratchpad RAM
256 input/output ports
Four to 31 locations of CALL/RETURN stack
Each instruction takes two clock cycles

7. PicoBlaze key features
 Twenty-one MIPS for CoolRunner II to 100
MIPS for Virtex 4
 Instruction size 16 to 18-bits
 Eight to 16 ,8-bit registers
 Size 76-96 slices (Virtex/Spartan) or 212
macrocells in CoolRunner-II

8. PicoBlaze Block Diagram

9. MicroBlaze:
MicroBlaze key features
 A Harvard 32-bit RISC processor
 MicroBlaze v4 is a three-pipeline-stage core
with 0.92 DMIPS/MHz
 MicroBlaze v5 is a five-pipeline-stage core
with 1.15 DMIPS/MHz
 The ALU, shifter, and 32 × 32 register file are
standard

10. MicroBlaze optional items
 Barrel shifter
 Array multiplier
 Divider
 Floating-point unit for add, subtraction,
multiply, divide, and comparison
 Data cache from 2-64 KB
 Instruction cache from 2 to 64 KB

11. MicroBlaze Core Block Diagram

12. Creating a PowerPC or MicroBlaze
design
The Xilinx EDK Toolset:
 EDK = Embedded Development Kit.
It is a set of tools used to build embedded
processing systems.
 i.e. Systems-On-Chip (SoCs)
• Processors (MicroBlaze, PowerPC)
• Memories (BRAM, DDR)
• Peripherals (UART, GPIO, Ethernet, Custom,
etc.)
…
 Provides a single environment for…
• Simulation
• Synthesis
• Compilation

13. Using EDK:
 Xilinx Platform Studio (XPS) - the actual tool.

14. Xilinx Plaform Studio

15. Using the PicoBlaze in an FPGA
Design
• The PicoBlaze microcontroller is supplied as a
VHDL source file, called KCPSM3.vhd
• Synthesis: Xilinx Synthesis Tool (XST) for logic
synthesis
• Simulation: ModelSim, pBlazSIM

16. Comparison
 PowerPC:
• Low power dissipation, power-conscious
applications
• Higher speed
• PicoBlaze:
• provides cost-efficient microcontroller-based
control and
simple data processing.
• PicoBlaze fits for8-bit application, such as
automotive and home appliance

17. Comparison
 MicroBlaze:
• Easy to use with EDK
•High “performance” softcore processor
- Most of instructions can be completed with 1
cycles
- Shorter pipeline, higher working frequency