An operating system for the MSP430 microcontroler: development of a FAT driver for TinyOS-2.x

Transcription

1 An operating system for the microcontroler: of a FAT driver for TinyOS-.x Merou, J.-M Friedt Association Projet Aurore, Besançon August 1, 009

2 Why an OS on a microcontroler? Sensor networks are under for a wide range of applications: a set of nodes spatily distributed monitor environment properties complex and reusable software dedicated operating system for such applications (low memory footprint & power consumption) TinyOS-.x is a free (BSD license) operating system (a.k.a executive environment) for embedded platforms Data acquisition during periodic wakeup sequences Data storage over a filesystem: radiofrequency links are not (yet) reliabl enough to answer our needs (+ consumption & communication range)

3 Presentation Two main systeme classes: Powerful but enrgy consuming platforms. Low power platforms will litte energy consumption. A sensor node must be autonomous use little electric power to run on batteries Objective: comfort of developing an application in the context of the former (OS) within the constraints of the latter: executive environment generates a monolithic application within the context close to that found in an OS.

4 CS DI VCC SCK 1 DO IRQ WP CD SW SHIELD WP CD SW 14 VBUS D- D+ VSERIE R4 VDD 4 5 k C36 >uf 6 IN1 GATE1 INGATE 3 IC 7 LTC1157 C Q N nf 3.3 IC5 3V3OUT USBDM USBDP _RESET OSCI OSCO TEST 5 D N3819 S G VSERIE 4 7 VDD D S 0 18 ONOFF1 1 9 B A 8 ONOFF D3 C 6 TXD RXD _RTS _CTS _DTR _DSR _DCD _RI CBUS0 CBUS1 CBUS CBUS3 CBUS4 VDD 4k7R R5 k Vservo SHOOT1 B A 1 SHOOT P1.5/TA0 P1.6/TA1 P1.7/TA P.0/ACLK P.1/TAINCLK P./CAOUT/TA0 P.3/CA0/TA1 P.4/CA1/TA P.5/ROSC P.6/ADC1CLK P.7/TA0 P3.0/STE0 P3.1/SIMO0 P3./SOMI0 P3.3/UCLK P3.4/UTXD0 C 13 AVCC DVSS AVSS P6./A P6.1/A1 P6.0/A0!RST/NMI TCK TMS TDI TDO/TDI XTIN XTOUT P5.7/TBOUTH P5.6/ALK P5.5/SMCLK JP7 JP3 1 3 JP JP6 VDD R C C9 5 4 R8 IC4 SHDN/ LBI REF 1n 3k FB MHz xt 6 1n C1 LBO/ VDD MAX1674 C10 3 L1 VDD 14 VDD VSS7 Node architecture USB MISO SCK VCC_SD MOSI CS JP1 IC3C VCC G Q4 A 1 VCCIO VCC D IC3A LED6 LED5 JP 4066D Q3 C1 C11 P1.4/SMCLK P1.3/TA P1./TA1 P1.1/TA0 P1.0/TACLK VEREF- VEREF+ XOUT/TCLK XIN VREF+ P6.7/A7 P6.6/A6 P6.5/A5 P6.4/A4 P6.3/A3 DVCC P3.5/URXD0 P3.6/UTXD1 P3.7/URXD1 P4.0/TB0 P4.1/TB1 P4./TB P4.3/TB3 P4.4/TB4 P4.5/TB5 P4.6/TB6 P4.7/TBCLK P5.0/STE1 P5.1/SIMO1 P5./SOMI1 P5.3/UCLK1 P5.4/MCLK 100n C13 C14 TDI R14 JP4 MPS_RST 10k TCK TMS 5 6 TDO 7 8 TCLK "JTAG" VDD Q1 LX 7 OUT 8 IC3P A non commerci platform to make sure we understand the whole configuration procedure of TinyOS-.x: F149 microcontroler (60 KB flash, KB de RAM) L1 C/A ET31 GPS receiver (RS3) removable SD card (SPI bus)

5 TinyOS-.x Compromise between low level programming and an operting system: set of routines structure including abstraction layers during the phase uses the nesc programming language generates a single monolithic application

6 Node integration Defined by two items: a declaration file a configuration directory

7 directory content projet.target.platform hardware.h C.nc P.nc PLATFORM = p r o j e t $ ( c a l l T O S M a k e i n c l u d e p l a t f o r m, msp ) projet : $ ( BUILD DEPS

8 directory content projet.target.platform hardware.h C.nc P.nc push includes, qw( %T/ c h i p s / msp430 %T/ c h i p s / msp430 / adc1 %T/ c h i p s / msp430 /dma %T/ c h i p s / msp430 / p i n s %T/ c h i p s / msp430 / t i m e r %T/ c h i p s / msp430 / u s a r t %T/ c h i p s / msp430 / s e n s o r s %T/ l i b / t i m e r %T/ l i b / s e r i a l %T/ l i b / power ) ) ; push qw( g c c=msp430 g c c mmcu=msp430x149 f n e s c t a r g e t=msp430 f n e s c no debug fnesc scheduler=tinyschedulerc, TinySchedulerC. TaskBasic, TaskBasic, TaskBasic, runtask, posttask ) ) ;

9 directory content projet.target.platform hardware.h C.nc P.nc #i n c l u d e " h a r d w a r e. h " c o n f i g u r a t i o n C { p r o v i d e s i n t e r f a c e I n i t ; i m p l e m e n t a t i o n { components P, Msp430ClockC ; I n i t = P ; P. Msp430ClockInit > Msp430ClockC. I n i t ;

10 directory content projet.target.platform hardware.h C.nc P.nc #i n c l u d e " h a r d w a r e. h " module P { p r o v i d e s i n t e r f a c e I n i t ; u s e s i n t e r f a c e I n i t a s M s p C l o c k I n i t ; u s e s i n t e r f a c e I n i t a s L e d s I n i t ; i m p l e m e n t a t i o n { command e r r o r t I n i t. i n i t ( ) { c a l l M s p C l o c k I n i t. i n i t ( ) ; c a l l L e d s I n i t. i n i t ( ) ; r e t u r n SUCCESS ; d e f a u l t command e r r o r t L e d s I n i t. i n i t ( ) { r e t u r n SUCCESS ;

11 Vidating the platform: blinking LEDs Application example: apps/blink #i n c l u d e " h a r d w a r e. h " c o n f i g u r a t i o n LedsC { p r o v i d e s i n t e r f a c e GenerIO a s Led0 ; p r o v i d e s i n t e r f a c e GenerIO a s Led1 ; p r o v i d e s i n t e r f a c e GenerIO a s Led ; u s e s i n t e r f a c e I n i t ; i m p l e m e n t a t i o n { components HplMsp430GenerIOC as GenerIOC, new Msp430GpioC ( ) as Led0Impl, new Msp430GpioC ( ) as Led1Impl ; components new NoPinC ( ) as LedImpl ; components P ; I n i t = P. L e d s I n i t ; // Raccorde l e v e n t i n i t c e l u i de P Led0 = Led0Impl ; Led0Impl > GenerIOC. Port16 ; Led1 = Led1Impl ; Led1Impl > GenerIOC. Port17 ; Led = LedImpl ; // No l e d on board

12 Beyond the LED driver: using an LCD #i n c l u d e " h a r d w a r e. h " c o n f i g u r a t i o n LcdC { p r o v i d e s i n t e r f a c e GenerIO a s LcdData0 ; [... ] p r o v i d e s i n t e r f a c e GenerIO a s LcdData3 ; p r o v i d e s i n t e r f a c e GenerIO a s LcdE ; p r o v i d e s i n t e r f a c e GenerIO a s LcdRS ; u s e s i n t e r f a c e I n i t ; i m p l e m e n t a t i o n { components HplMsp430GenerIOC as GenerIOC, new Msp430GpioC ( ) as LcdData0Impl, [... ] new Msp430GpioC ( ) as LcdData3Impl, new Msp430GpioC ( ) as LcdEImpl, new Msp430GpioC ( ) as LcdRSImpl ; components P ; I n i t = P. L c d I n i t ; LcdData0 = LcdData0Impl ; LcdData0Impl > GenerIOC. Port4 ; [... ] LcdData3 = LcdData3Impl ; LcdData3Impl > GenerIOC. Port7 ; LcdE = LcdEImpl ; LcdEImpl > GenerIOC. Port3 ; LcdRS = LcdRSImpl ; LcdRSImpl > GenerIOC. Port ;

13 Exploiting the LCD driver Bitwise sign manipulation // E c r i t un demi o c t e t void writedb ( uint8 t v ) { v = v & 0 x0f ; i f ( v a l & LCD DATA0) c a l l LcdData0. s e t ( ) ; e l s e c a l l LcdData0. c l r ( ) ; i f ( v a l & LCD DATA1) c a l l LcdData1. s e t ( ) ; e l s e c a l l LcdData1. c l r ( ) ; i f ( v a l & LCD DATA) c a l l LcdData. s e t ( ) ; e l s e c a l l LcdData. c l r ( ) ; i f ( v a l & LCD DATA3) c a l l LcdData3. s e t ( ) ; e l s e c a l l LcdData3. c l r ( ) ;

14 LCD results An interface useful for debugging and interacting with a user

15 Asynchronous communication RS3: two-way communication protocol. TinyOS model. packets are embedded for network routing ( IP header on ethernet) incompatible with a GPS receiver (NMEA sentences do not comply with this encapsulation) use of raw RS3 communication

16 RS3 communication Raw RS3 interface The public interface. The configuration. #i n c l u d e " h a r d w a r e. h " c o n f i g u r a t i o n P l a t f o r m S e r i a l C { p r o v i d e s i n t e r f a c e S t d C o n t r o l ; p r o v i d e s i n t e r f a c e UartStream ; p r o v i d e s i n t e r f a c e UartByte ; i m p l e m e n t a t i o n { components new Msp430Uart1C ( ) a s UartC, p r o j e t S e r i a l P ; UartStream = UartC. UartStream ; UartByte = UartC. UartByte ; StdControl = p r o j e t S e r i a l P. Control ; p r o j e t S e r i a l P. Msp430UartConfigure < UartC. Msp430UartConfigure ; p r o j e t S e r i a l P. R eso ur ce > UartC. R es our ce ; p r o j e t S e r i a l P. R e s o u r c e R e q u e s t e d > UartC. R e s o u r c e R e q u e s t e d ; components LedsC ; p r o j e t S e r i a l P. Leds > LedsC ;

17 RS3 communication Raw RS3 interface The public interface. The configuration. m s p u a r t u n i o n c o n f i g t m s p u a r t p r o j c o n f i g = { { ubr : UBR 3KHZ 4800, umctl : UMCTL 3KHZ 4800, s s e l : 0 x01, pena : 0, pev : 0, spb : 0, c l e n : 1, l i s t e n : 1, mm: 0, c k p l : 0, u r x s e : 0, u r x e i e : 1, u r x w i e : 0, u r x e : 0, u t x e : 1 ;

18 Example of an OEM GPS receiver Continuous position information reception Uses ASCII sentences (NMEA) = termination character defines the end of the sentence Asynchronous communication (RS3, 4800 bauds) Bandwidth: 144 B/s $GPRMC, ,A, ,N, ,W, , , ,, 1 1 $GPGGA, , ,N, ,W, 1, 0 5, 8., 5. 1,M, 5. 5,M,, $GPRMC, ,A, ,N, ,W, , , ,, 1 F $GPGGA, , ,N, ,W, 1, 0 5, 8., 5. 4,M, 5. 5,M,, C

19 Synchronous communication SPI: asymetric master-slave protocol. N + signs to communicate with N slaves : MOSI (Master Out Slave In), MISO (Master In Slave Out) and N Chip Select signs high bandwidth (shared clock) hardware implementation on most microcontrolers.

20 Use of the SPI bus Implementation of a module managing a Secure Digit card (SD) for non volatile mass storage. SD programmation JTAG communication USB LCD SPI compatible Large storage capacity. Default buffer size 51 bytes, might be reduced during config. Lack of native drivers for TinyOS-.x Blocking model selected

21 s : Efficient data saving. Direct data retriev. Acquired data are structured TinyOS model Which filesystem? simple and hence sml memory footprint/power consumption cross-platform. designed for older personn computers. still in use.

22 Presentation of FAT Access through the Master Boot Record (MBR) Partition Clusters File Allocation Table Implemented as multiple modules Bandwidth: 1.6 kb/s

23 Presentation of FAT Access through the Master Boot Record (MBR) Partition Clusters File Allocation Table Implemented as multiple modules Bandwidth: 1.6 kb/s Fich_1 Fich_ FAT FF FF

24 Presentation of FAT Access through the Master Boot Record (MBR) Partition Clusters File Allocation Table Implemented as multiple modules Bandwidth: 1.6 kb/s

25 Example: periodic acquisition and data storage in a file / D cl e n c he m e n t du timer / e v e n t v o i d Timer0. f i r e d ( ) { c a l l f a t C o n t r o l. s t a r t ( ) ; / Fat f i n i de s i n i t / e v e n t v o i d f a t C o n t r o l. s t a r t D o n e ( e r r o r t e r r o r ) { i f ( e r r o r == SUCCESS) c a l l f i l e C o n t r o l. s t a r t ( ) ; / F i l e f i n i t son i n i t / e v e n t v o i d f i l e C o n t r o l. s t a r t D o n e ( e r r o r t e r r o r ) { i f ( e r r o r == SUCCESS) c a l l ReadStream. postbuffer ( tampon+5, ( uint16 t )NBLINES) ; / La l e c t u r e e s t f i n i e / event void ReadStream. bufferdone ( e r r o r t result, uint8 t buf, uint16 t count ) { i f ( r e s u l t == SUCCESS) c a l l f i l e. w r i t e ( tampon, count +5) ; // E c r i t u r e c a l l f a t C o n t r o l. s t o p ( ) ; // Tout t e i n d r e e v e n t v o i d f a t C o n t r o l. stopdone ( e r r o r t e r r o r ) { i f ( e r r o r == SUCCESS) c a l l f i l e C o n t r o l. s t o p ( ) ; wakeup instrument wakeup init SD open file RS3 sentences acquisition data storage close file/sd deep sleep timer

26 Development of an application using the drivers for : Data acquisition and storage on an SD card on the embedded device Data transfer to computer using SD card reader Use of the data to generate a graph Track characteristics sentences Duration 11 hours File size: 4.7 MB

27 Working environment close to the one familiar for under an OS easy port of a C program thanks to nesc transparent port from one platform to another easier code maintenance, focus on the innovative work our contribution: a driver for data storage (result of anog to digit conversion, RS3) on a FAT formatted SD card (SPI bus) The driver has been vidated on a Crossbow Telos board, further s include testing on a MicaZ platform (AVR processor)

28 Questions Further readings: [in French]