External Interfaces and Software Tools for Electronic Blocks

1
External Interfaces and Software Tools for
Electronic Blocks

• Shawn Nematbakhsh
• University of California, Riverside

Thesis Defense Dr. Frank Vahid, Chairman Dr.
Harry Hsieh Dr. Walid Najjar
2
eBlocks

• What are eBlocks?
• Single-function blocks that snap together to
  build useful simple systems.
• Each block contains its own microcontroller to
  process data.
• Three types of blocks Input, output,
  computation.
• Current protocol completely binary YES/NO.
• eBlock Project Goals
• Allow construction of simple monitor/control
  systems in a short period of time.
• Allow inexperienced users to build simple systems
  that would otherwise be impossible.

3
Overview

• eBlock External Interfacing
• Internet
• Telephone
• PDA
• eBlock Software Tools
• eBlock Simulator
• Programmable eBlock
• Sample Application
• Parking Lot Monitor

4
eBlock External Interfacing

• eBlock systems designed to be entirely
  self-contained.
• Sensors, buttons, lights, buzzers, etc all
  implemented as stand-alone eBlocks
• Would be useful to interface with external
  non-eBlock systems.
• Devices and technologies already exist to perform
  tasks that would be inefficient to implement as
  stand-alone eBlocks.
• Three interfaces created Internet, Telephone,
  PDA.

5
Network eBlock

• Intended for long-range monitoring of eBlock
  systems.
• Takes input from eBlock system, output to
  ethernet interface.
• On startup gets IP of listening host gateway
  networking information from user.
• Constantly streams UDP packets with eBlock status
  to listening host.

Network eBlock
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Network eBlock

• Listening socket program on host defines
  behavior.
• Ships with application outputting date/time of
  input change to web page.
• Users can define own behavior with C API.
• Many possible applications
• Record and display every packet received.
• Send email when YES packet is received.
• Output packet data to IRC chat channel.
• Any network application required completely
  customizable.

7
Phone Dialer eBlock

• Takes eBlock input, on startup is configured with
  a target telephone number. Connects to telephone
  line.
• When YES packet is received dialer opens line
  and calls target number, waits 30 seconds, and
  hangs up.
• Intended for remote emergency alerts such as
  intrusion or disaster detection.

Dialer eBlock
8
Phone Relay eBlock

• Reverse of phone dialer block takes a
  telephone input and outputs to an eBlock system.
• User dialing in enters code to stream YES or
  NO packets to system. Packets sent continuously
  until next call.
• Intended for remote control of eBlock systems
• Sample application toggling lights in house
  while on vacation to deter theft.

Phone Relay eBlock
9
Palm Logger

• Palm PDA application used to record history of
  input changes.
• Data saved on Palm system in text file for later
  analysis.
• eBlock input fed through converter device to
  translate TTL to RS232 for Palm use.
• Solves problem of automatic monitoring of eBlock
  status.

10
eBlock Software Tools

• eBlock External Interfacing
• Internet
• Telephone
• PDA
• eBlock Software Tools
• eBlock Simulator
• Programmable eBlock
• Sample Application
• Parking Lot Monitor

11
eBlock Simulator

• eBlock simulator allows drag-and-drop layout and
  testing of eBlock systems.
• Simulation-based testing of eBlock systems
  without physical construction, saving
  construction time.
• Input, computation, and output blocks supported.
• Input blocks simulated with user input toggling
  state.
• Output blocks simulated with visual alerts.
• Computation blocks display current state.
• Stepwise simulation or real-time.

12
eBlock Simulator

• As design is layed out, table keeps track of
  blocks and connections. Cycles disallowed.
• Simulation algorithm
• Evaluate() produces block output based on inputs
  block type. UpdateDisplay() changes display to
  reflect output.
• Running time O(VE) (Vblocks,Ewires) because
  of topological sort

Simulate(table Tn) OrderedTopologicalSort(
T). for i 1 to n do Evaluate(Orderedi)
UpdateDisplay(Orderedi))
13
eBlock Simulator

• eBlock Simulator widely used.
• Basis for current version in use by over 500
  people.
• Allows worldwide eBlock use without distributing
  sets of physical blocks.
• Simulator useful for testing and feedback.
• Allows eBlock designers to judge user
  understanding of blocks.
• Able to test and change block customization
  without physical construction. Ex 2-input logic
  user interface.
• Lack of cycles a limitation certain systems
  cannot be simulated.
• Software simulator generally well-liked by users.
• What if physical systems could be built using the
  simulator interface?

14
Programmable eBlock

• Idea Use simulator to layout eBlock system.
  Replace multiple computation blocks with a single
  custom block synthesized to perform the same
  exact function for implementation.

15
Programmable eBlock Tool

• Design laid out using simulator drag-and-drop
  interface.
• Different input blocks replaced with INPUT
  point.
• Output blocks replaced with OUTPUT point.
• Represent input and output points into
  programmable block.
• Once design completed, SYNTHESIS button is
  clicked.
• Ordered table created from users design.
• C struct representation copied into code file
  along with static code to step through table.
• File is compliable using PICC to program onto a
  microcontroller without any code needing to be
  written by user.
• Usable by advanced users or engineers without
  programming experience.

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Programmable eBlock Tool

• Algorithm
• GetOrdered runs on PC, produces ordered
  representation in C.
• Step runs on microcontroller once each time a
  packet is received or timeout occurs. Both O(VE).

GetOrdered(table Tn) Call Simulate(T)
Keep Ordered array and output to C code Step
(table Orderedm) for i1 to m do
evali Evaluate(Orderedi) output
evalm

const struct block blocksNUMBLOCKS-1,-1,INPUT
,0,0,0,0,0,-1,SPLITTER,0,0,0,0,1,-1,TOGGLE,0,0
,0,0,1,-1,INVERTER,0,0,0,0,3,2,OR,0,0,0,0,4,
-1,OUTPUT,0,0,0,0
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Programmable eBlock

• After C code generation, PIC microcontroller can
  be programmed.
• Zero programming knowledge required by user
  simply compile and download to chip.
• Programmable block implemented as enclosure with
  ZIF socket.
• Allows easy chip placement after programming.
• Problem One UART per microcontroller.
• Separate microcontroller needed for each set of
  inputs and outputs included.
• Extra microcontrollers serve only to receive
  input and send output.
• Communicate with single master microcontroller to
  perform all computation.

18
Virtual Blocks

• Blocks in programmable eBlock tool do not
  necessarily have to exist at physical level.
• Blocks implemented in C code for programmable
  block.
• No need for stand-alone eBlock implementing the
  same function.
• Size of virtual eBlock library does not have to
  be limited.
• Selecting a virtual block from library as simple
  as selecting from menu and dragging.
• Fine-grained functional blocks can be created
  without worry of bloat.
• Certain blocks requiring user customization are
  easier to set by computer. Ex dial-switch timer.
  
• Programmable blocks can be a mix of actual
  physical blocks and virtual blocks which exist
  only in software.

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Virtual Blocks

• Two additional blocks created for programmable
  eBlock tool.
• Sequencer block used for pattern matching of
  previous input.
• Eight previous inputs represented with 1, 0,
  .
• Ex 101 outputs YES only if previous
  input was YES, previous to that NO, previous
  to that YES.
• Replaces gate-level pattern matching.
• N-Timer block used to monitor time with
  continuous YES packets received.
• Value N from 1-59,999 specified by user
• If only YES packets have been received for N
  continuous
• seconds then YES is outputted for one
  timeout period
• (2 secs).

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Virtual Block Applications

• Sequencer
• Can be used for passcode systems.
• Also useful for error correction dont sound
  alarm unless motion sensor detects several
  consecutive YES inputs. First input may be false
  alarm.
• N-Timer
• Useful for systems that perform long-range
  timing.
• Difficult for users to easily specify large
  periods of time on-block Dial and DIP switches
  dont work well for customizing large values.
• Best solution is to specify using computer
  simply type desired value in.

21
Sample Application

• eBlock External Interfacing
• Internet
• Telephone
• PDA
• eBlock Software Tools
• eBlock Simulator
• Programmable eBlock
• Sample Application
• Parking Lot Monitor

22
Parking Lot Monitor

• Meter-free time-limited spaces usually monitored
  manually.
• Chalk tire marks used to determine time elapsed.
• Labor-intensive Monitor must constantly walk
  around lots.
• Automate parking lot monitoring using
  electronics.
• Keep track of time elapsed in parking space.
• Wirelessly alert car driver several minutes
  before expiration.
• Wirelessly alert lot monitor at expiration.

23
Parking Lot Monitor from Traditional eBlocks

• Infrared receiver / transmitter placed across
  parking space.
• Logic blocks set to trigger when pulse goes low
  (time exceeded) and infrared beam is broken (car
  still in space).
• Two extended pulse generators performing timing
  of deadline time and deadline time minus 5
  minutes so driver gets chance to move car before
  time expires.

Buzzer
Buzzer
IR Beam Tx
Wireless Rx Block (to attendant)
Pulse Gen. Block (deadline)
2-IN Logic Block (01)
Wireless Tx Block
Wireless Rx Block (to user)
Pulse Gen. Block (deadline--)
2-IN Logic Block (01)
Wireless Tx Block
IR Rx Block
Splitter Block
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Parking Lot Monitor with Dialer

• Dialer used to send alerts to user and monitor.
• Advantage Replaces six wireless receiver,
  transmitter, and buzzer blocks with two dialer
  blocks.
• Advantage Not range-limited like wireless
  eBlocks.
• Advantage Doesnt require external buzzer to
  carry around.
• Disadvantage Requires user to have mobile phone.
  
• Disadvantage Requires phone line near parking
  space.

IR Beam Tx
Pulse Gen. Block (deadline)
2-IN Logic Block (01)
Phone Dialer
Pulse Gen. Block (deadline--)
2-IN Logic Block (01)
Phone Dialer
IR Rx Block
Splitter Block
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Parking Lot Monitor with Programmable eBlock

• Replaces five blocks used for timing with a
  single programmable eBlock.
• Programmable block created with splitter and two
  N-Timers.
• Advantage Five to one block reduction.
• Advantage Easier to design and understand for
  user.

N- Time
IR Beam Tx
Split
N- Time
Phone Dialer
Programmable eBlock
IR Rx Block
blocksNUMBLOCKS-1,-1,INPUT,0,0,0,0,0,-1,SPL
ITTER,0,0,0,0,1,-1,NCOUNTER,14,16,0,0,1,-1,NCO
UNTER,12,128,0,0,2,-1,OUTPUT,0,0,0,0,3,-1,OUTP
UT,0,0,0,0
Phone Dialer
26
Parking Lot Monitor from Components

• Parking lot monitoring system also implemented
  with traditional components.
• With schematic from web, construction required
  8.5 hrs compared to 1.25 hrs for traditional
  eBlock construction.
• Microcontroller programming required for
  component version, but not necessary for eBlock
  construction. Component version not buildable for
  non-programmers.
• Component version allows more flexibility, but
  eBlock design meets all requirements in this case.

27
Conclusion and Future Work

• Conclusion
• eBlocks have been expanded to use external
  interfaces, allowing a wide range of powerful new
  systems to be created.
• eBlock software tools were created that are being
  built on and improved today. These tools allow
  large scale use and experiment on eBlocks, and
  are the basis for eBlock synthesis.
• Future Directions
• Expand the library of virtual blocks to include
  many more functions useful for systems.
• Improve the synthesis tool to perform advanced
  optimizations such as design minimization and
  partitioning across multiple blocks.