Home Wireless Control Students Lee Blum Ehud Ravitz Instructor Konstantin Sinyuk Mid Semester Presentation Project A

Project ’ s General Description Create a data and control network over household appliances. Aim of the Project

Project ’ s General Description – Cont. Each household appliance will have an End Point embedded within it. In every room in the house, an Access Point will control over all the End Points in the room using a Bluetooth wireless connection. All the Access Points will communicate with one another through a wired CAN network. Network Structure

Household Appliance Final Detailed Definitions End Points contain a Microchip PIC18F452 and a Phillips Bluetooth unit, which is controlled by the PIC using UART. The PIC controls over the household appliance it is embedded within, according to Bluetooth data transfers with the Access Point. End Points UART PIC18F452 Phillips Bluetooth Unit BT

Final Detailed Definitions – Cont. Access Points contain a Microchip PIC18F458 and a Philips Bluetooth Unit. Each Access Point, located in a different room of the house, can communicate with up to seven local End Points using Bluetooth. The PIC controls the Phillips Bluetooth Unit using UART. Extra E 2 PROM memory stores the Access Point’s database of local and total End Points. A CAN 2.0B on the PIC communicates between different Access Points, enabling control of an Access Point on End Points in different rooms. Access Points

Final Detailed Definitions Access Point CAN Connection To other Access Points CAN Connection To other Access Points CAN controller End Point End Point UARTI2C BT Phillips BT UnitDB of End Points on E 2 PROM PIC18F458

General Block Design Access Point End Point Legend:

Specifications Phillips Bluetooth Philips Components V GHz to GHz Operating Frequency Class 2 (0 dBm nominal) Transmit Output Power Up to 15m (with integral antenna)Operating range Less than 1E-3 BERReceiver Sensitivity Embedded software stack supporting an HCI interface Embedded Software Point to Multipoint (up to 7 slaves) Master/Slave switching supported Network Topology USB v1.1, UART at up to 921 kbps (low voltage serial interface) Interface 3 to 3.4V (or direct power from USB connection) Power Supply Idle < 2mA File transfer 70mA Peak < 100mA Current consumption -10 to + 55°COperating Temperature -40 to + 85°C Storage Temperature 45 x 48 x 7mmDimensions

Specifications – Cont. Microchip PIC18F452/8 DC – 40 MHz Operating Frequency 32KBytes Internal Program Mem BytesData Memory 256 BytesData EEPROM Memory 2: 18 ; 8: 21Interrupt Sources A, B, C, D, EI/O Ports 4Timers Addressable USART, MSSP (+ CAN on 8) MSSP, CAN, Serial Communications YesParallel Communications (PSP) 8 input channels 10-bit Analog- to-Digital Converter 2: 0 ; 8: 2 Analog Comparators 2: No ; 8: YesAnalog Comparators VREF Output Yes Programmable Low Voltage Detect YesProgrammable Brown-out Reset 2: No ; 8: YesCAN Module 75 InstructionsInstruction Set Yes40-pin PDIP

CAN max. freq. is 1Mbps. Bluetooth effective max. is 750KB/sec. PIC to BT UART connection is in 115,200 bps. PIC’s upgraded frequency is 40MHz. Therefore, the CAN connection can support a system with four Access Points, each one transferring one End Point’s data, as expected. Work Frequencies

Implementation’s Advantages The Bluetooth Protocol is a standard. Making generic as possible to produce. Should be embedded in all household appliances, of all manufacturers. Strong enough to handle intended rate of communications (as seen in previous slide) since it is mainly short data transfers, mainly for control functions. Availability of Similar Digital Lab projects on other platforms. PC and DSP code could be set as base for the PIC development, with changes from a multi-threaded program to a single-thread, and considering the PIC’s relative weaknesses to the previous platforms.

Communication Algorithm Access Point (AP) is always Master. End Points (EP) are always Slaves. AP Scans for updated EPs in area every 60 sec. AP Calls EP when allocated. EP stores AP’s BD Address to know who is his Master. EP refuses other APs trying to connect him when is with a Master. Packets sent from APs to EPs: –Command –Inquiry for Data Packets sent from EPs to APs: –Data in response to inquiry / command

Debugging Methods To debug the applications running on the PIC, we use the Debugger, supplied with the PIC Development Kit. The debugger is connected to the PIC through the PIC Demo Board 2, and is used through the MPLab development environment. We will also use the LCD, supplied on the PIC Demo Board 2, for faster, easier and specific tests.

Software Demands C18 compiler in the MPLab Development Environment to write C code to run on the PIC. We will implement the following modules: 1.UART communication 2.Bluetooth stack implementation 3.LCD printing 4.The main module, to implement the application’s state machine. Will use and operate modules 1-3.

1. UART module The Uart module includes: An initialization function to set flags and buffer size. A write function to the UART. Uses interrupts, and a string of bytes in size “length”, that acts as a software simulated write-buffer. A read function that reads one byte from the buffer, when it is not empty.

2. Bluetooth module The Bluetooth module includes: An initialization function to set the communication with the Bluetooth and parameters. A send function that sends a data package with size “length” to a specific end point. A receive function that reads a message, when available, from a specific end point. A search function to locate and set up local End-Points.

3. LCD module The LCD module includes: An initialization function to initialize communication with the LCD screen.An initialization function to initialize communication with the LCD screen. A write function to write a message to be displayed on the LCD.A write function to write a message to be displayed on the LCD.

4. The main module The main module includes: An initialization function that initializes modules 1-3 and all variables used in the main module.An initialization function that initializes modules 1-3 and all variables used in the main module. An endless loop to manage the network using modules 1-3.An endless loop to manage the network using modules 1-3. Using interrupt-driven UART functions the PIC manages the BT unit.Using interrupt-driven UART functions the PIC manages the BT unit. End Points use the main module to handle I/O from the appliance and communicate with their local Access Points.End Points use the main module to handle I/O from the appliance and communicate with their local Access Points. In Part B, Access Points will use the main module to contact one-another using CAN.In Part B, Access Points will use the main module to contact one-another using CAN.

* End Points also handle input from the appliance. In part B, the main module in Access Points will handle input/output from CAN module routines as well. UART routines Control the Phillips unit LCDRoutines BluetoothRoutines Manage the Bluetooth protocol Output Debug Debug Interrupt-Driven The Main Module* Manages the household network Module dependency diagram

Time Table 14/ 5/03 - Writing the LCD module. 21/ 5/03 - Testing Bluetooth. 28/ 5/03 - Testing Prev. impl. of BT Piconet. 4/ 6/03 - Implementing BT stack on the PIC. 11/ 6/03 - Writing Point to Point connection module. 18/ 6/03 - Writing Multi-Point connection module. 25/ 6/03 - Writing Application Layer. 1/ 8/03 - Writing the progress report. 1/11/03 - Final Date.

To be continued