2/26/2009
Jay Brasch Daniel Kopelove
Kirk Nichols Katrina Bossert

• Create a sensing vehicle with the following functionality
– Natural gas sensor
– Geiger counter
– Streaming video
• Control various aspects of the vehicle
– Orientation and position of vehicle
– Orientation and position of camera (two-axis control)
Kirk Nichols

• SCAB I rev c
– New Parts
• ENC28J60
• AtTiny24
• ATF16LV8C
• SCAB II rev a
– New additions
• LPC 2377
• Motor Relays
• Ethernet PHY Module
• Peripherals
– Geiger counter constructed, awaiting radioactive source for sufficient testing
Kirk Nichols

Base Station
Laptop LabVIEW
AtTiny24 ATF16LV8C
USB
Joystick
Vuzix
HUD
(Peripherals)
Ethernet
PHY/MAC
Layer
NXP 2214/2377
Servo
(3)
DC
Motor
Vehicle Control
System Information
Battery
Level
Debug
Port
Kirk Nichols
Sensing Ports
Pulse
(2)
ADC
(2)
Geiger
(Velocity)
Gas
Sensor
UART
(5)
+
ATF750
CPLD
I 2 C
(3)
(Range
Sensors)
(Compass)

• Peripheral Microcontroller
– 10 MHz
– SPI interface
– Offload the following peripheral interfaces from the LPC 2214/2377
• 8 ADCs
• 12 External interrupt pins
Kirk Nichols

• Multiplex serial communication such that all serial communication can be controlled with one UART port on LPC 2214/2377.
• Programmable with WinCUPL
• 3.3V Source
Kirk Nichols

 Advantages over the LPC2214 Microcontroller
• Ethernet MAC with associated DMA Controller
 Access to PHY chip via MII
 Put Ethernet work into hardware instead of software
• Real-Time Clock
•RTOS software available
 Disadvantages
•Only 3.3V source needed instead of 3.3/1.8V, therefore consumes more power
•Need to Port Code
Kirk Nichols

• I/F to 802.3 compliant MAC system on the
LPC2377
• Media Independent Interface Management
(MIIM)
• Internal 2.5V regulator
• 50MHz VCO
• Connects to RJ-45 with Magnetics
• LQFP-48
Daniel Kopelove

• 100Base-TX/FX
– Increased regularity thanks to fiber
• Link status interrupts
Software:
• Olimex Board – RTOS+UIP
Daniel Kopelove

KS8721BL
Daniel Kopelove

• Command set (from LabVIEW to scab)
• Data packets (from SCAB to LabVIEW)
• LabVIEW is an intelligent controller (sends low level commands to SCAB)
• Data packets are static size
Daniel Kopelove

Field (offset) Timestamp
(0x0)
Format U32
Sequence Num
(0x3)
U32
Opcode (0x7) Optional Raw
Data (0x9)
U16 U64
Timestamp – excessively late packet arrivals
Sequence num – used for statistics
Opcode – one of the predefined commands
Optional Raw Data – A command may have some extra data, the format of this data depends upon which opcode accompanies it,
Null padded, even word aligned
Daniel Kopelove

• Current implemented commands
Command Code
Set speed pulse width
Set vehicle heading servo pulse width
0x0010
0x0011
Set pan servo pulse width
Set tilt servo pulse width
Send data
Set periodic data transmission interval
Restart system
Reset DC motor controller
Self Destruct
0x0012
0x0013
0x0020
0x0021
0x0030
0x0031
0x0BAD
Daniel Kopelove

Field (offset) Timestamp
(0x00)
Format U32
Field
(offset)
Format
Sequence Num
(0x03)
U32
Valid (0x07)
U64
Geiger counts last sec (0x0E)
U16
Geiger counts last 5 sec
(0x11)
U16
Geiger counts
Last X sec
(0x13)
U16
Geiger counts last Y sec
(0x15)
U16
Speed pulse last W sec (0x17)
U16
Field
(offset)
Format
Speed pulse
Last X sec
(0x19)
U16
Speed pulse last Y sec
(0x1B)
U16
Speed pulse last Z sec
(0x1D)
U16
Gas LEL (0x1F)
U16
Daniel Kopelove

Field (offset) A/D 2 (0x21) Compass
(0x23)
Format U16 U32
I2C 1 (0x27)
U32
I2C 2 (0x2B)
U32
Field (offset) Battery stack V
1 (0x2F)
Format U16
Battery stack V
2 (0x31)
U16
Servo 1 pulse width (0x33)
U16
Servo 2 pulse width (0x35)
U16
Field (offset)
Format
Servo 3 pulse width (0x37)
U16
H&S Data
(0x39)
U32
Speed pulse width (0x3D)
U16
Daniel Kopelove

Katrina Bossert

• Successful
– Reasonable user interface
– Web browser and successful IP address connection
• Problems
– LabVIEW USB Driver
– Limitations in programming (e.g. you must request a specific size of data from a TCP/IP connection)
Katrina Bossert

Goggles
(incorporate
C++ code)
USB Joystick
& LabVIEW Driver
Serial
Communication
LabVIEW
Keyboard Control
Video Streaming
TCP IP and
Communication protocol
Katrina Bossert

• “Don’t do it”
– Threading never as simple as it seems
• Advantages
– Manages system timers and interrupts
– Convenient scheduling of recurring tasks
• Our implementation
– Latencies as high as 100 ms acceptable
– Short, simple tasks
Jay Brasch

{ void ethernetController( void *pvParameters )
DataType Data1, Data2
{ while( true) vTaskDelayUntil( &xLastWakeTime, CYCLE_RATE_MS )
// Request data from the sensors.
if(checkEthernetQueue(&Data1) if (Data.HighPriority) processCriticalTask(Data1) else processNormalTask(Data1)
}
}
}
Jay Brasch

Two battery sources for maximum isolation
12 V (26 W) Consumption (W) 7.6V (21 W) Consumption(W)
SCAB 4
Ethernet Controller 3
Router
Geiger Counter
Total
6
2
15
Motor 20
Ethernet Camera 6
Servos 2
Total 26
*35W motor battery readily available
Jay Brasch

• Goal: Handle unexpected conditions gracefully
– “Heartbeat” packet sent periodically
– Battery state sensing
– Relays
• Reset motor controller
• Reset router manually or 90 dB buzzer
– Lost communication procedures
• Wait and attempt reconnect
• Move 5s opposite most recent heading
• Execute Start of Day (SOD) task
Jay Brasch

Task
Poll Tiny
Poll Batt
Poll Link
Poll Periph 1
Poll Command Queue 1
Poll Speed 1
Poll Gas
Heartbeat
Comm. INT
1
1
3
1
1
Time 1 2 3 4 5 6 7 8 9 10 11
1 x x x x x x x x x x x
Jay Brasch

Task
Request from Tiny
Open/Close relays
Actuate Servos
Change motor speed
Send Data
1
3
1
1
Time
1
Jay Brasch

• Milestone 1
– SCAB installed on vehicle
• Controlling motors
• Controlling camera
– Embed video stream in LabVIEW
– LabVIEW controls vehicle via RS232
• Milestone 2
– SCAB acts as network host
• Transmits telemetry data to LabVIEW interface
– LabVIEW acts as network host
• Transmits control commands to SCAB
– System can run 30 minutes from battery
Katrina Bossert

Kirk
LabVIEW
SCAB
Vehicle
HUD
Ethernet
Communication
Router
Katrina Bossert
Katrina
Jay
Dan

Kirk Nichols

LPC 2377
Kirk Nichols

Kirk Nichols

Kirk Nichols

• u08 pkt1[] = {0x00,
• 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x16,
• 0xb6, 0x98, 0x95, 0x3f, 0x08, 0x06, 0x00, 0x01,
• 0x08, 0x00, 0x06, 0x04, 0x00, 0x01, 0x00, 0x16,
• 0xb6, 0x98, 0x95, 0x1f, 0x0a, 0x00, 0x01, 0x02,
• 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a, 0x00,
• 0x01, 0x14 };
• IO3DIR |= 0x00000002;
• IO3SET = 0x00000002;
• initMAC();
• write_ptr = ReadETHReg(EWRPTL);
• write_ptr |= (ReadETHReg(EWRPTH) << 8);
• WriteMacBuffer(pkt1, 51);
• write_ptr = ReadETHReg(EWRPTL);
• write_ptr |= (ReadETHReg(EWRPTH) << 8);
• WriteCtrReg(ETXNDL, write_ptr);
• WriteCtrReg(ETXNDH, (write_ptr >> 8));
• SetBitField(ECON1,ECON1_TXRTS);
Kirk Nichols

Kirk Nichols