Embedded Micros module 11 rev c.pptusers.wpi.edu/~rjduck/Embedded Micros module 11 rev c.pdf– Need to be familiar with micros (as well as logic design) Jim Duckworth, WPI 13 Embedded

Jim Duckworth, WPI Embedded Microprocessors1

Embedded Microprocessors

Module 11


Topics

• Microcontrollers versus FPGAS

– What is the best for your application?

• Debugging embedded designs

– Chipscope Pro and Agilent FPGA Dynamic Probe

– Use VHDL/Verilog models of system components (e.g. SDRAM)

• Xilinx Virtex-4,5,6 Spartan-6, 7 Series (Kintex etc)

– DSPslices, Ethernet MAC, integrated processors

• Adding Microcontrollers to FPGAs

– Picoblaze, Microblaze, Power PC (405 and 440), ARM

• Xilinx Zynq-7000

– Programmable System on Chip (SoC)

• Dual ARM Cortex-A9 MPCore

• Plus FPGA logic with up to 218,600 LUTs and 437,200 FFs


Microcontrollers versus FPGAs

• Microcontrollers

– Execute compiled programs written in ‘C’ or Assembler

• Program may be on the micro or in external flash memory

• Micro fetches instructions, decodes, manipulates data or I/O

– Sequential execution

• Requires multiple clock cycles for most operations

– Can be easily optimized for battery powered operations

• Only wake up in response to external interrupts

– Limited I/O of standard logic

• FPGAs

– ‘Sea of gates’ can be configured for any required logic

– Very good for high-speed parallel data processing (e.g. graphics, networks)

– Lots of I/O – versatile logic interface (LVDS etc)

– Can be easily partitioned into different functional blocks

– Not appropriate for simple control applications


Digital Controller Board – Virtex II FPGA

SDRAM

Config

PROMLVDS

Interface

FPGA

Ethernet Transceiver


FPGA Functional Blocks


DDR SDRAM Controller – 128 byte writes


PPL Transceiver – Based on Virtex 4


Transceiver Box



Debugging Embedded Designs

• VHDL and Verilog models of standard devices

– Micron models of all SDRAM devices – simulates behavior

– Use as part of Test Benches

• will report functional errors (initialization, setup/hold time violations)

• Xilinx ChipScope Pro

– Poor man’s logic analyzer!

– Connected and analyzed through JTAG port

– See on-line introduction (with CoreGen)

• Agilent FPGA Dynamic Probe

– Interfaces through special core inside FPGA


Embedded Software Tools

CPU

Logic Design Tools

I/O

FPGA

Memory

Logic Design Tools

FPGA +

Memory + IP +

High Speed IO

(4K & Virtex)


CPU

Inte

gra

tio

n o

f F

un

ctio

ns

Inte

gra

tio

n o

f F

un

ctio

ns

TimeTime

Logic Design Tools


Logic + Memory

+ IP +

Processors +

RocketIO

(Virtex-II Pro)

Programmable Systems

usher in a new era of system

design integration

possibilities

Programmable Systems

usher in a new era of system

design integration

possibilities

Integration in System Design


Embedded Processors

• Soft core processors – use on any FPGA– Picoblaze 8-bit microcontroller

• Programmed in assembler

• Very useful for handling serial IO (UART, SPI interface) and replacing complex state machines

– Microblaze 32-bit microcontroller

• Use Xilinx EDK – base system builder (Program in ‘C’)

• Now part of IP Catalog Core Generator

• Hard Processor cores – IBM Power PC 405and 440 32/64-bit Processor

• 16 KB data cache and 16 KB instruction cache

• Virtex-5 FXT FPGA Power PC 440 (550MHz) 1100+ DMIPS

– Dual Arm Cortex-A9 MP Core (1GHz) – on Zynq SoC Devices

• Can add and mix multiple processors!– Need to be familiar with micros (as well as logic design)



Picoblaze overview


Picoblaze Block diagram


Micro versus Logic


Picoblaze resources – very low!


Microblaze 32-bit Soft Processor


Microblaze Overview

MicroBlaze Core Block Diagram



Embedded DevelopmentTool Flow Overview

Data2MEM

Bitstream

Compiler/Linker

(Simulator)

C Code

Debugger

Standard Embedded SWDevelopment Flow

CPU code in on-chip memory

?

CPU code in off-chip memory

Download to Board & FPGA

Object Code

Standard FPGA HWDevelopment Flow

Synthesizer

Place & Route

Simulator

VHDL/Verilog

?

Download to FPGA

Microblaze MCS - Tool Flow (Xilinx PG116)


Microblaze MCS - FPGA Resources Used

• Basys3 board (Artix-7 XC7A35T)

– See tutorial


Utilization Available %

LUT 704 20,800 3.4

FF 300 41,600 0.7

BRAM 8 50 16

Xilinx Zynq-7000 SoC Device

• Dual-core Cortex-A9

• DDR3 memory

controller

• Ethernet, USB, SDIO

• SPI, UART, I2C

• Logic

– Logic Cells

– Block RAM

– DSP Slices

– Dual-channel, 12-bit,

1MSPS ADC


ZedBoard – Zynq 7020


ZedBoard Example Design*

*Avnet Zedboard “Getting Started Guide”


ZedBoard Example Design*

*Avnet Zedboard “Getting Started Guide”


Digilent ZYBO Zynq-7010 ($125)


Documents

Embedded Micros module 11 rev c.pptusers.wpi.edu/~rjduck/Embedded Micros module 11 rev c.pdf– Need to be familiar with micros (as well as logic design) Jim Duckworth, WPI 13 Embedded