MSD Project 10236 Configurable Control Platform for Unmanned Vehicles Detailed Design Review Joe Pinzone Alex Mykyta Roberto Stolfa Robert Ghilduta Jason.

MSD Project 10236Configurable Control Platform

for Unmanned Vehicles

Detailed Design Review

Joe PinzoneAlex Mykyta

Roberto StolfaRobert Ghilduta

Jason Stanislawski

System Overview

System OverviewControl Code Processor (CCP)

Gumstix: TEXAS INSTRUMENTS OMAP3530

• ARM Cortex-A8 GP CPU• C64x DSP• Store/execute Simulink control code• 256MB flash (OS / Control Code)• 256MB RAM• Power management IC

• High-speed serial bus to I/O Controller

System OverviewInput/Output Controller (IOC)

XILINX SPARTAN 3E FPGA w/ PLASMA uC CORE

•Arbitrates sensor and actuator input/output

•Provides sensor data to CCP in common format through shared, dual-port memory

•Provides analog and digital I/O interface connectors, broken out on I/O Breakout Board

System OverviewI/O Breakout Board (IOB)

• The only vehicle-specific hardware •Breaks out IOC header to individual sensors and actuators

• Physically separate package from Controller Platform

• Generally no processing done here

System OverviewPower, Control Code Processor, I/O Controller are physically:

– separable– stacked– enclosed

System OverviewPower, IOC, CCP = Vehicle Controller Platform, separate from IOB

Power

*All values are worst case

Power

Rail Current Required Power Required

1.2 V 0.088 A 0.106 W

2.5 V 0.045 A 0.113 W

3.3 V 0.322 A 1.060 W

4 V 0.400 A 1.600 W

5 V 0.129 A 0.643 W

*All values are worst case

PowerTPS43000-Based

SW-MODE PSU

OUTPUT 5V/1.5A

TPS43000-Based

SW-MODE PSU

OUTPUT 5V/1.5A

5V/0.25A5V/0.25A

4V/0.5A4V/0.5A

3.3V/0.5A3.3V/0.5A

2.5V/0.1A2.5V/0.1A

1.2V/0.1A1.2V/0.1A

IOB, ADC, DAC

CCP

IOCBattery PackBattery Pack

PowerFRONT END CONDITIONING

TEXAS INSTRUMENTS TPS43000• SEPIC (buck/boost) configuration• 1.8 – 9V Input• 6A output with proper FET switches • Synchronous Rectification (+eff)

TPS43000 (PSU FRONT END)

PowerSECONDARY STAGELINEAR REGULATORS

LM317 ADJ. LDO• Low-drop-out• Vout 1.25 –> 5+ volts• Use for 5V, 4V• Up to 1.5A output

TLV70012 for 1.2V/200mATLV70025 for 2.5V/200mATPS73733 for 3.3V/0.50A

Power SummaryMax Nom Units

Total Useful Pwr 3.524 2.890 Watts

Total Current 0.984 0.792 Amps

Power to LDOs 4.918 3.958 Watts

Efficiency of SM 0.900 0.900

Total Reqd. Pwr 5.464 4.398 Watts

Supply Voltage 4.800 4.800 Volts

Supply Current 1.138 0.916 Amps

Battery Capacity 2.700 2.700+ A-h

Est. Time 2.372 2.947 Hours

Est Efficiency 0.645 0.657

NomenclatureFirmware:

– Program code that runs on the embedded processors. This does not include the Control Code, which will always be referred to specifically.

Rigidware: – The HDL containing the “image” of the FPGA gate configuration. This

may contain RAM/ROM initialization images and basic boot loader to initialize and load the stored firmware. This term generally pertains only to the IOC, since it is the only programmable-logic device in the system.

Software:– Any program that runs on the user PC for the purpose of programming,

configuring, compiling, or monitoring the embedded system.

IO Controller Module

• Arbitrates IO from the CCP• Physically separable from CCP

– Can be used as independent data logger or used in future projects.

• Implemented using a Xilinx Spartan 3E FPGA (XCS500E-PQ208)

FPGA Selection

• FPGA chosen for highest gate & largest pin count• BGA is not desirable due to board routing complexity

Package

Device VQ100 CP132 TQ144 PQ208 FT256 FG320 FG400 FG484

XC3S100E X X X

XC3S250E X X X X X

XC3S500E X X X X X

XC3S1200E X X X

XC3S1600E X X X

IOC Rigidware

Plasma Core

Dual Port RAM1kB

Serial Controller

SPI Bus:PM Storage & SD Card

Dedicated UART

~40kB RAM

A D

SPI Master

CE

CK

DO

DI

Tx Rx

High Speed Serial

To CCP

System Clock Counter

IRQ

IRQ

A

D

PWM ReaderPWM

GeneratorIO Port IO Port IO Port IO Port

ADC Controller

CK

SO

SI

CS-ADC

CS-DAC

NOTE: All IO Ports, ADC Controller, Dedicated UART and SD/PM SPI module are capable of generating interrupts.

8 8 8 8 8 8

Main RAM

• XC3S500E has 45KB of Block Memory

• Approximately 40 KB will be used for Plasma CPU

• RAM preloaded with boot loader

SPI FLASH & MMC

• Application code is stored on SPI Flash– Boot loader loads

application into RAM

• Same SPI bus is used for an SD card for logging– All typical SD cards

support standard MMC protocol

System Clock Counter

• Provides timing information

• Sourced from 50 MHz clock which allows for integer division to decade increments of time.

Dedicated UART

• Hardwired to USB-UART transceiver

• Load new application code

• Debug system during operation

CCP Communication

• Dual port ram allows for independent operation

• High speed serial interface used to access shared RAM

• Interrupt signals provided to and from CCP

Analog Controller

• Finite state machine responsible for acquiring analog data from ADC– Data available for direct

access from CPU address space

• Configures reference voltage DAC

PWM Controller

• FSM that arbitrates servo PWM generation and reading

• Generator is configurable to provide servo format or full range duty cycles

Configurable IO Ports

• Each pin can be configured as input, output, or special function

• Special functions include configurable SPI, I2C and UART modules

• IP provided by OpenCores

SPI Core I2C

Core UART GPIO

CE CK DO DI SDA SCL Tx Rx

A D D D DA A A

Special FunctionSelect

8

Configurable IO Ports

• MAV peripheral set only requires 1 port• Preliminary logic estimates show that 5 ports should

be possible

IOC Hardware

Xilinx Spartan 3EXC3S500E-4

PQ208

FPGA Config. ICXCF02S

SPI FLASH PM Storage

SST25VF032B

50.0000 MHz Clock

14.7456 MHz Clock

USBà Dual UART

FT2232

EEPROMAT93C46E

8 Channel 16-bit ADC

ADS1178

SD/MMC Card

socket

Bidirectional Voltage

TranslatorTXB0108

Voltage Reference

DACTLV5623C

IO Ports

PWM OutPWM In

[-]

SPI

SPI

RxTx

High SpeedSerial

(or future GPMC)

IRQ

IRQ

JTAG

Config.

JTAG

JTAG

JTA

G H

ea

der

USB Mini-B

USB

Digital IO HeaderAnalog Header

BankVref

Bidirectional Voltage

TranslatorTXB0108

BankVref

Bidirectional Voltage

TranslatorTXB0108

BankVref

Bidirectional Voltage

TranslatorTXB0108

BankVref

Rx Tx

Header to CCP

8

8 8 8 8 8 8

[+]

8

Programming Interface

• USBUART converter does most of the work for us• PM FLASH is programmed from UART• Second UART is provided for CCP configuration

FLASH & SD Card

• SST’s 4MB FLASH stores application program• Shares SPI Bus with SD Card for data logging and

removable storage

CCP Interface

• High speed serial interface to CCP along with interrupt requests

• Pins on FPGA and header are reserved specifically for implementing GPMC in the future

FPGA Configuration

• On power-up, FPGA is automatically configured by the XCF02S which stores rigidware.

• Rigidware can be changed via JTAG interface

Analog to Digital Converter

• Simultaneous samples of 8 channels

• Supports differential inputs• Adjustable sampling range

– Range is digitally controlled by adjacent DAC

Digital IO

• PWM signals connected directly to IOB (3.3v levels)

• Configurable IO Ports have adjustable logic levels.– User supplies voltage

reference– TXB0108 detects direction of

communication without the need for direction control

Logic Cost Analysis

LUTs

Plasma Core 3306

CCP Interface 300

PWM IO Controller 300

Analog Controller 230

Configurable IO Port 710

Number of IO Ports: 5

Total LUTs Used: 7686

Available LUTs 9312

Remaining LUTs 1626

• Design with 5 IO ports uses approximately 80% of available logic– 20% for uncertainty in

estimates and potential overhead for PAR of large designs.

Throughput Estimation

• Dummy DAQ program written for MAV set of peripherals– Single sample can be executed in ~420 clock

cycles @ 25 MHz– Assuming SPI communication to IMU is done

without interrupts, CPU must stall for duration of transfer (~200 cycles @ 2 MHz)

– Results in theoretical sample rate of 30 kHz

I/O Breakout Board

I/O Breakout Board

DEVICE LIST FOR UAV IOB

Analog Devices IMU

Tyco Electronics GPS

Airspeed Differential Pressure Sensor

Altimeter Absolute Pressure Sensor

Thermistor

I/O Breakout Board

Diff V_IN max. ( V+) - ( V-) +/- 3.1 VV_IN max. V+ or V- 5.1 VV_IN min. V+ or V- - 0.1V

TI ADS1178

Sensor Vout Max Vout Min V- Vref

Airspeed 4.7 0.2 2.45 2.25

Altitude 4.5 0.5 2.5 2.0

Temperature 4.986 0.229 2.493 2.38

V- CalculationAirspeed Sensor:(4.7V + .2V)/2 = 2.45V Altitude Sensor:( 4.5V + .5V)/2 = 2.5V Temperature Sensor:(4.986V + .229V) / 2 = 2.493V

Vref CalculationAirspeed Sensor:(4.7V - .2V)/2 = 2.25V Altitude Sensor:( 4.5V - .5V)/2 = 2.0V Temperature Sensor:(4.986V -.229V) / 2 = 2.38V

I/O Breakout BoardDigital Peripherals: Tyco Electronics GPS – UART (NMEA) Analog Devices IMU – SPI Telemetry (P10231) – I2C, SPI, UART

I/O Breakout Board

MUX IC Manual Override:2 – Quad 2 to 1 multiplexers

I/O Breakout Board

Molex 24 position connector

Standard DSUB Connectors

Pitot-Static Probe (Airspeed)

Ram Air Pressure

Stagnation (Static)

Control Code Processor

CCP Overview

• OMAP– ARM

• Linux

– Fixed point TI DSP• DSP/BIOS

– running RT workshop Control System

• Sensor data is memory mapped with DMA from the IO controller over a dedicated link

Incremental Design• Gumstix (target for MSD 2)

– Ready-to-run system on a module– Self-sustained (low to no dependency count)– Readily available, non-existent lead time

• Topedo SOM– Smaller + lower power consumption than Gumstix– Higher throughput achievable

• Custom Board– Cheapest, fastest, most efficient yet most complicated

solution• An implementation meeting every need marked

“HIGH” has to be met before proceeding

Gumstix• Board requires nothing power• 2 expansion slots breakout McBSP and GPMC• Board lacks DMA support for GPMC• Implementation will use DMA with McBSP

– DMA will be configured to routinely read data from McBSP and copy to a location in memory without interrupts

– Slower than GPMC, uses less pins• Interface is well known• Target development time: 4 weeks

Torpedo

• Second revision– Motivations: smaller board, GPMC with DMA

becomes possible• Uses OMAP3530 (just as the Gumstix)• Product comes with verified schematics and

layouts• Release date - late December• Expected price - $150• Target development time: 4 weeks

Custom board

• Reasons to improve on Torpedo– OMAP3525 is cheaper than the 3530– TPS65920 consumes less power, requires less

layout area (fewer discrete components are required)

• Development time– Software and interface overlaps with Torpedo– Schematics and layout can mostly be reused

McBSP with DMA

McBSP cont’d

• Multi-channel Buffered Serial Port– (High speed serial)– Asynchronous Synchronous supported

• DMA would be used to limit the use of the ARM processor

• Maximum clock speed (bit speed) can use L4 clock (96MHz)– FPGA may not be able to reach this

• Bit speed may need to be halved and channel count double

GPMC

GPMC cont’d• General Purpose Memory Controller (Interface)

– Typical SRAM interface• Asynchronous/Synchronous supported

• Allows external memory devices to be mapped into OMAP’s memory address space

• Burst speeds (where Row address is latched) of 400MB/s supported– in reality speed is limited by FPGA’s IO buffers

• Gumstix cannot use this interface because DMA pins that would be used to notify L2 Memory of outdated data are not accessible

Control Code Processor - Software

•

Matlab Integration

End User Workflow Software Required:

Matlab/Simulink Real-time Workshop TI C6x DSP Toolchain Code Sourcery

ARM Toolchain

Vehicle Profiler

Control Code Uploader

Control Code Processor OS

Linux OpenEmbedded

Framework TI DSP-Bridge

Control Code Loader Daemon

Control Code Wrapper

Budget ITEMPRODUCT COST

EST OUR COST EST

Power Controller $4.50 $0.00

Linear Regulators $2.80 $0.00

Switching Components $7.00 $7.00

Spartan 3E FPGA $24.90 $24.90

FPGA Config IC $4.25 $4.25

FLASH Boot Memory $2.56 $0.00

Oscillator $2.63 $2.63

Oscillator $2.63 $2.63

USB to dual RS232 $6.99 $6.99

EEPROM for FT2232 $0.37 $0.37

8ch 16-bit ADC $25.42 $0.00

Bidirectional Voltage Translator

$2.00

$0.00

8-bit DAC $2.48 $0.00

Gumstix $170.00 $170.00

Gumstix Dev Board $0.00 $50.00

Board to Board Conex $25.00 $25.00

Misc Passives $30.00 $30.00

External Connectors $50.00 $50.00

Enclosures $20.00 $20.00

PCB FAB $116.00 $248.00

Control Platform Total $499.53 $641.77

Controller Platform

Budget

24 pin, 0.1" Header Pins 6.84 $6.84

Dual Flip-Flop 1.00 1.00

Quad 2 to 1 Multiplexer 0.40 0.40

10k POT 6.68 $6.68

Airspeed Sensor 11.70 $0.00

Altitude Sensor 5.80 $0.00

Temperature Sensor 34.00 $0.00Analog Devices IMU $527.44 $0.00

GPS 61.50 $0.00

Pitot Static Probe 160.00 $0.00

Mounting Chuck 35.00 $0.00

UAV IOB Total $527.44 $13.52

UAV I/O Breakout

Budget

Final Product This Project

Total $1,026.97 $655.29