X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=doc%2Fhtml%2Ftep109.html;h=56b758c178bcb27b6bde2b724929fac11e1419ef;hb=b7e372c3aa2f1da307407397da3b032df4ac4d49;hp=d353a66f19039496d826fbcae08daf131bf455a0;hpb=826bb539a6c489db5b216e7326bf693ec67d15e5;p=tinyos-2.x.git diff --git a/doc/html/tep109.html b/doc/html/tep109.html index d353a66f..56b758c1 100644 --- a/doc/html/tep109.html +++ b/doc/html/tep109.html @@ -3,9 +3,9 @@
- +Type: | Documentary |
---|---|
Status: | -Draft | Final |
TinyOS-Version: | 2.x |
Author: | -David Gay, Phil Levis, Wei Hong, Joe Polastre, and Gilman Tolle |
Draft-Created: | 10-Jun-2006 | -
Draft-Discuss: | TinyOS Developer List <tinyos-devel at mail.millennium.berkeley.edu> | -David Gay, Philip Levis, Wei Hong, Joe Polastre, and Gilman Tolle |
Note
This memo documents a part of TinyOS for the TinyOS Community, and @@ -314,15 +305,15 @@ requests discussion and suggestions for improvements. Distribution of this memo is unlimited. This memo is in full compliance with TEP 1.
This memo documents how sensor drivers are organized in TinyOS and how sets of sensor drivers are combined into sensor boards and sensor platforms, along with general principles followed by the components that provide access to sensors.
This section describes the basic organization principles for sensor drivers in TinyOS.
For background, a sensor can be attached to the microcontroller on a @@ -367,15 +358,16 @@ sensor itself. The naming of the sensor driver components SHOULD reflect the specifc name of the sensor, and MAY provide a component with a generic name for application authors who only care about the general class of the sensor.
-This document takes no position on the meaning of the values returned -by sensor drivers. They MAY be raw uninterpreted values or they MAY -have some physical meaning. If a driver returns uninterpreted values, -the driver MAY provide additional interfaces that would allow -higher-level clients to obtain information needed to properly -interpret the value.
+This document requires that sensor components specify the range (in +bits) of values returned by sensor drivers, but takes no position on +the meaning of these values. They MAY be raw uninterpreted values or +they MAY have some physical meaning. If a driver returns uninterpreted +values, the driver MAY provide additional interfaces that would allow +higher-level clients to obtain information (e.g. calibration +coefficients) needed to properly interpret the value.
A sensor HIL component MUST provide:
The getSignificantBits() call MUST return the number of significant bits in the reading. For example, a sensor reading taken from a 12-bit -ADC MUST return the value "12".
+ADC would typically return the value 12 (it might return less if, e.g., +physical constraints limit the maximum A/D result to 10-bits).Sensor driver components SHOULD be named according to the make and model of the sensing device being presented. Using specific names gives the developer the option to bind to a particular sensor, which @@ -467,8 +460,8 @@ implementation { }
Sensors with a richer interface than would be supported by the SID interfaces MAY provide a HAL component in addition to a HIL component.
@@ -482,9 +475,11 @@ with commands for sampling and controlling the sensor device.For example:
@@ -497,78 +492,124 @@ implementation { }
Because the same physical sensor can be attached to TinyOS platforms -in many different ways, the organization of sensor drivers SHOULD -reflect the distinction between sensor and sensor interconnect.
-Sensor components commonly exist at three levels: -platform-independent, sensorboard-dependent, and -platform-dependent. Factoring a sensor driver into these three pieces -allows for greater code reuse when the same sensor is attached to -different sensorboards or platforms.
-Platform-independent sensor driver components for a particular sensor, -like protocol logic, when in the core TinyOS 2.x source tree, SHOULD -be placed into "tos/chips/<sensor>", where <sensor> reflects the make -and model of the sensor device being supported. When not a part of the -core source tree, this directory can be placed anywhere as long as the -nesC compiler recieves a -I directive pointing to the sensor's -directory. However, not all sensors have a sufficiently large amount -of platform-independent logic to justify a separate "chips" -directory. Sensor chips are more likely to be digital sensors than -analog sensors, for example.
-A sensor board is a collection of sensor components with a fixed name, -intended for attachment to multiple platforms. Each sensor board MUST -have its own directory named <sensorboard>. Default TinyOS 2.x sensor -boards are placed in "tos/sensorboards/<sensorboard>", but sensor -board directories can be placed anywhere as long as the nesC compiler -receives a -I directive pointing to the sensor board's directory.
-Both sensors and sensor boards MUST have unique names. Case is -significant, but two sensor boards MUST differ in more than case. This -is necessary to support platforms where filename case differences are -not significant.
-Each sensor board directory MUST contain a .sensor file. This file -is a perl script which gets executed as part of the ncc nesC -compiler frontend. It can add or modify any compile-time options -necessary for a particular sensor board. It MAY modify the following -perl variables, and MUST NOT modify any others:
+Sensors are associated either with a particular sensor board or with a +particular platform. Both sensors and sensor boards MUST have unique +names. Case is significant, but two sensor (or sensor board) names +MUST differ in more than case. This is necessary to support platforms +where filename case differences are not significant.
+Each sensor board MUST have its own directory whose name is the sensor +board's unique name (referred to as <sensorboard> in the rest of this +section). Default TinyOS 2.x sensor boards are placed in +tos/sensorboards/<sensorboard>, but sensor board directories can be +placed anywhere as long as the nesC compiler receives a -I directive +pointing to the sensor board's directory. Each sensor board directory +MUST contain a .sensor file (described below). If the +sensor board wishes to define any C types or constants, it SHOULD +place these in a file named <sensorboard>.h in the sensor board's +directory.
+A sensor board MAY contain components that override the default TinyOS +demo sensors. This allows the sensor board to easily be used with +TinyOS sample applications that use the demo sensors. If a sensor +board wishes to override the default demo sensor:
+It MUST provide a generic component named DemoSensorC with the +following signature:
++provides interface Read<uint16_t>; +provides interface DeviceMetadata; ++
It MAY provide a generic component named DemoSensorNowC with the +following signature:
++provides interface ReadNow<uint16_t>; +provides interface DeviceMetadata; ++
This component SHOULD sample the same sensor as DemoSensorC.
+It MAY provide a generic component named DemoSensorStreamC with the +following signature:
++provides interface ReadStream<uint16_t>; +provides interface DeviceMetadata; ++
This component SHOULD sample the same sensor as DemoSensorC.
+These components MUST be an alias for one of the sensor board's usual +sensors, though they change the precision of the sensor if necessary. +For instance, if DemoSensorC is an alias for a 20-bit sensor that +provides a Read<uint32_t> interface, DemoSensorC would still +provide Read<uint16_t> and would include code to reduce the +precision of the aliased sensor.
+When the ncc nesC compiler frontend is passed a -board=X option, +it executes the .sensor file found in the sensor board directory +X. This file is a perl script which can add or modify any +compile-time options necessary for the sensor board. It MAY modify the +following perl variables, and MUST NOT modify any others:
+If a sensor is associated with a platform P rather than a sensor +board, then that platform MUST ensure that, when compiling for +platform P, all directories needed to compile that sensor's +component are added to the TinyOS search path (see [TEP131] for +information on how to set up a TinyOS platform).
+A particular sensor is typically supported by many components, +including the HIL and HAL components from Sections 2 and 3, A/D +conversion components (for analog sensors), digital bus components +(e.g., SPI, for digital sensors), system services (timers, resource +and power management, ...), glue components (to connect sensors, +sensor boards and platforms), etc. These components can be divided +into three classes: sensorboard-dependent, platform-dependent and +platform-independent. The sensorboard and platform MUST ensure +(Section 4.1) that all these components can be found at compile-time.
+Because the same physical sensor can be used on many platforms or +sensor boards, and attached in many different ways, to maximize code +reuse the organization of sensor drivers SHOULD reflect the +distinction between sensor and sensor interconnect. The sensor +components SHOULD be platform-independent, while the sensor +interconnect components are typically sensorboard or +platform-dependent. However, some sensors (e.g. analong sensors) will +not have a sufficiently large amount of platform-independent logic to +justify creating platform-independent components.
+The following guidelines specify how to organize sensor and sensor +interconnect components within TinyOS's directory hierarchy. These +guidelines are only relevant to components that are part of the core +source tree. The string <sensor> SHOULD reflect the make and model +of the sensor device.
If the sensor board wishes to define any C types or constants, it -SHOULD place these in a file named <sensorboard>.h in the sensor -board's directory.
-A sensor board directory MAY contain a "chips" directory, with -subdirectories for each of the sensors connected to the sensor board. -If a "chips" subdirectory is used, sensorboard-dependent driver -components needed to connect platform-independent logic to a -particular attachment for that sensor SHOULD be placed in -"<sensorboard>/chips/<sensor>".
-Components needed to connect the platform-independent sensor driver -components or sensorboard-dependent components to the hardware -resources available on a particular platform SHOULD be placed in -"tos/<platform>/chips/<sensor>". In addition, components for a sensor -that only exists on a particular platform SHOULD be placed in a such a -directory.
-Sensors that exist as part of a larger chip, like a MCU internal -voltage sensor, SHOULD be placed in a subdirectory of the chip's -directory. "tos/<chip>/sensors/<sensor>".
-The .platform and .sensor files need to include enough -I -directives to locate all of the necessary components needed to support -the sensors on a platform and/or sensorboard.
-All of these directory organization guidelines are only intended for -code that will enter the core source tree. In general, sensor -components can be placed anywhere as long as the nesC compiler -receives enough -I directives to locate all of the necessary pieces.
[TEP2] | TEP 2: Hardware Abstraction Architecture |
[TEP108] | TEP 108: Resource Arbitration |
[TEP115] | (1, 2) TEP 115: Power Management of Non-Virtualized Devices |
[TEP115] | (1, 2, 3) TEP 115: Power Management of Non-Virtualized Devices |
[TEP131] | TEP 131: Creating a New Platform for TinyOS 2.x |
The Analog sensor requires two components
tos/platforms/telosa/chips/s1087/HamamatsuS1087ParC.nc +// HIL for the HamamatsuS1087 analog photodiode sensor generic configuration HamamatsuS1087ParC() { provides interface Read<uint16_t>; provides interface ReadStream<uint16_t>; provides interface DeviceMetadata; } implementation { + // Create a new A/D client and connect it to the Hamamatsu S1087 A/D + // parameters components new AdcReadClientC(); Read = AdcReadClientC; @@ -671,12 +727,15 @@ tos/platforms/telosa/chips/s1087/HamamatsuS1087ParP.nc #include "Msp430Adc12.h" +// A/D parameters for the Hamamatsu - see the MSP430 A/D converter manual, +// Hamamatsu specification, Telos hardware schematic and TinyOS MSP430 +// A/D converter component specifications for the explanation of these +// parameters module HamamatsuS1087ParP { provides interface AdcConfigure<const msp430adc12_channel_config_t*>; provides interface DeviceMetadata; } implementation { - msp430adc12_channel_config_t config = { inch: INPUT_CHANNEL_A4, sref: REFERENCE_VREFplus_AVss, @@ -696,8 +755,8 @@ implementation { }
The Binary sensor gets a bit more complex, because it has three components:
tos/platforms/telosa/UserButtonC.nc +// HIL for the user button sensor on Telos-family motes configuration UserButtonC { - provides interface Get<bool>; - provides interface Notify<bool>; + provides interface Get<bool>; // Get button status + provides interface Notify<bool>; // Get button-press notifications provides interface DeviceMetadata; } implementation { + // Simply connect the button logic to the button HPL components UserButtonLogicP; Get = UserButtonLogicP; Notify = UserButtonLogicP; @@ -731,13 +792,15 @@ implementation {tos/platforms/telosa/UserButtonLogicP.nc +// Transform the low-level (GeneralIO and GpioInterrupt) interface to the +// button to high-level SID interfaces module UserButtonLogicP { provides interface Get<bool>; provides interface Notify<bool>; provides interface DeviceMetadata; uses interface GeneralIO; - uses interface GpioInterrupt; + uses interface GpioInterrupt; } implementation { norace bool m_pinHigh; @@ -749,6 +812,8 @@ implementation { command error_t Notify.enable() { call GeneralIO.makeInput(); + // If the pin is high, we need to trigger on falling edge interrupt, and + // vice-versa if ( call GeneralIO.get() ) { m_pinHigh = TRUE; return call GpioInterrupt.enableFallingEdge(); @@ -762,6 +827,7 @@ implementation { return call GpioInterrupt.disable(); } + // Button changed, signal user (in a task) and update interrupt detection async event void GpioInterrupt.fired() { call GpioInterrupt.disable(); @@ -773,9 +839,9 @@ implementation { task void sendEvent() { bool pinHigh; pinHigh = m_pinHigh; - + signal Notify.notify( pinHigh ); - + if ( pinHigh ) { call GpioInterrupt.enableFallingEdge(); } else { @@ -789,6 +855,9 @@ implementation {tos/platforms/telosa/HplUserButtonC.nc +// HPL for the user button sensor on Telos-family motes - just provides +// access to the I/O and interrupt control for the pin to which the +// button is connected configuration HplUserButtonC { provides interface GeneralIO; provides interface GpioInterrupt; @@ -809,8 +878,8 @@ implementation { }
The Digital sensor is the most complex out of the set, and includes six components:
tos/platforms/telosa/chips/sht11/SensirionSht11C.nc -generic configuration SensirionSht11C() { +// HIL interface to Sensirion SHT11 temperature and humidity sensor +generic configuration SensirionSht11C() { provides interface Read<uint16_t> as Temperature; provides interface DeviceMetadata as TemperatureDeviceMetadata; provides interface Read<uint16_t> as Humidity; provides interface DeviceMetadata as HumidityDeviceMetadata; } implementation { + // Instantiate the module providing the HIL interfaces components new SensirionSht11ReaderP(); Temperature = SensirionSht11ReaderP.Temperature; @@ -847,6 +918,7 @@ implementation { Humidity = SensirionSht11ReaderP.Humidity; HumidityDeviceMetadata = SensirionSht11ReaderP.HumidityDeviceMetadata; + // And connect it to the HAL component for the Sensirion SHT11 components HalSensirionSht11C; enum { TEMP_KEY = unique("Sht11.Resource") }; @@ -861,12 +933,18 @@ implementation {tos/chips/sht11/SensirionSht11ReaderP.nc +// Convert Sensirion SHT11 HAL to HIL interfaces for a single +// client, performing automatic resource arbitration generic module SensirionSht11ReaderP() { provides interface Read<uint16_t> as Temperature; provides interface DeviceMetadata as TemperatureDeviceMetadata; provides interface Read<uint16_t> as Humidity; provides interface DeviceMetadata as HumidityDeviceMetadata; - + + // Using separate resource interfaces for temperature and humidity allows + // temperature and humidity measurements to be requested simultaneously + // (if a single Resource interface was used, a request for temperature would + // prevent any humidity requests until the temperature measurement was complete) uses interface Resource as TempResource; uses interface Resource as HumResource; uses interface SensirionSht11 as Sht11Temp; @@ -874,12 +952,13 @@ generic module SensirionSht11ReaderP() { } implementation { command error_t Temperature.read() { - call TempResource.request(); - return SUCCESS; + // Start by requesting access to the SHT11 + return call TempResource.request(); } event void TempResource.granted() { error_t result; + // If the HAL measurement fails, release the SHT11 and signal failure if ((result = call Sht11Temp.measureTemperature()) != SUCCESS) { call TempResource.release(); signal Temperature.readDone( result, 0 ); @@ -887,6 +966,7 @@ implementation { } event void Sht11Temp.measureTemperatureDone( error_t result, uint16_t val ) { + // Release the SHT11 and signal the result call TempResource.release(); signal Temperature.readDone( result, val ); } @@ -894,12 +974,13 @@ implementation { command uint8_t TemperatureDeviceMetadata.getSignificantBits() { return 14; } command error_t Humidity.read() { - call HumResource.request(); - return SUCCESS; + // Start by requesting access to the SHT11 + return call HumResource.request(); } event void HumResource.granted() { error_t result; + // If the HAL measurement fails, release the SHT11 and signal failure if ((result = call Sht11Hum.measureHumidity()) != SUCCESS) { call HumResource.release(); signal Humidity.readDone( result, 0 ); @@ -907,12 +988,14 @@ implementation { } event void Sht11Hum.measureHumidityDone( error_t result, uint16_t val ) { + // Release the SHT11 and signal the result call HumResource.release(); signal Humidity.readDone( result, val ); } command uint8_t HumidityDeviceMetadata.getSignificantBits() { return 12; } + // Dummy handlers for unused portions of the HAL interface event void Sht11Temp.resetDone( error_t result ) { } event void Sht11Temp.measureHumidityDone( error_t result, uint16_t val ) { } event void Sht11Temp.readStatusRegDone( error_t result, uint8_t val ) { } @@ -923,6 +1006,8 @@ implementation { event void Sht11Hum.readStatusRegDone( error_t result, uint8_t val ) { } event void Sht11Hum.writeStatusRegDone( error_t result ) { } + // We need default handlers as a client may wire to only the Temperature + // sensor or only the Humidity sensor default event void Temperature.readDone( error_t result, uint16_t val ) { } default event void Humidity.readDone( error_t result, uint16_t val ) { } } @@ -930,20 +1015,27 @@ implementation {tos/platforms/telosa/chips/sht11/HalSensirionSht11C.nc +// HAL interface to Sensirion SHT11 temperature and humidity sensor configuration HalSensirionSht11C { + // The SHT11 HAL uses resource arbitration to allow the sensor to shared + // between multiple clients and for automatic power management (the SHT11 + // is switched off when no clients are waiting to use it) provides interface Resource[ uint8_t client ]; provides interface SensirionSht11[ uint8_t client ]; } implementation { + // The HAL implementation logic components new SensirionSht11LogicP(); SensirionSht11 = SensirionSht11LogicP; + // And it's wiring to the SHT11 HPL - the actual resource management is + // provided at the HPL layer components HplSensirionSht11C; Resource = HplSensirionSht11C.Resource; SensirionSht11LogicP.DATA -> HplSensirionSht11C.DATA; SensirionSht11LogicP.CLOCK -> HplSensirionSht11C.SCK; SensirionSht11LogicP.InterruptDATA -> HplSensirionSht11C.InterruptDATA; - + components new TimerMilliC(); SensirionSht11LogicP.Timer -> TimerMilliC; @@ -974,6 +1066,9 @@ implementation {tos/platforms/telosa/chips/sht11/HplSensirionSht11C.nc +// Low-level, platform-specific glue-code to access the SHT11 sensor found +// on telos-family motes - here the HPL just provides resource management +// and access to the SHT11 data, clock and interrupt pins configuration HplSensirionSht11C { provides interface Resource[ uint8_t id ]; provides interface GeneralIO as DATA; @@ -981,8 +1076,9 @@ configuration HplSensirionSht11C { provides interface GpioInterrupt as InterruptDATA; } implementation { + // Pins used to access the SHT11 components HplMsp430GeneralIOC; - + components new Msp430GpioC() as DATAM; DATAM -> HplMsp430GeneralIOC.Port15; DATA = DATAM; @@ -994,6 +1090,7 @@ implementation { components new Msp430GpioC() as PWRM; PWRM -> HplMsp430GeneralIOC.Port17; + // HPL logic for switching the SHT11 on and off components HplSensirionSht11P; HplSensirionSht11P.PWR -> PWRM; HplSensirionSht11P.DATA -> DATAM; @@ -1007,9 +1104,10 @@ implementation { InterruptDATAC.HplInterrupt -> HplMsp430InterruptC.Port15; InterruptDATA = InterruptDATAC.Interrupt; + // The arbiter and power manager for the SHT11 components new FcfsArbiterC( "Sht11.Resource" ) as Arbiter; Resource = Arbiter; - + components new SplitControlPowerManagerC(); SplitControlPowerManagerC.SplitControl -> HplSensirionSht11P; SplitControlPowerManagerC.ArbiterInit -> Arbiter.Init; @@ -1020,7 +1118,12 @@ implementation {tos/platforms/telosa/chips/sht11/HplSensirionSht11P.nc +// Switch the SHT11 on and off, and handle the 11ms warmup delay module HplSensirionSht11P { + // The SplitControl interface powers the SHT11 on or off (it's automatically + // called by the SHT11 power manager, see HplSensirionSht11C) + // We use a SplitControl interface as we need to wait 11ms for the sensor to + // warm up provides interface SplitControl; uses interface Timer<TMilli>; uses interface GeneralIO as PWR; @@ -1031,17 +1134,19 @@ implementation { task void stopTask(); command error_t SplitControl.start() { + // Power SHT11 on and wait for 11ms call PWR.makeOutput(); call PWR.set(); call Timer.startOneShot( 11 ); return SUCCESS; } - + event void Timer.fired() { signal SplitControl.startDone( SUCCESS ); } command error_t SplitControl.stop() { + // Power the SHT11 off call SCK.makeInput(); call SCK.clr(); call DATA.makeInput(); @@ -1057,6 +1162,41 @@ implementation { }
Here we show the organization of the sensor board directory for the +mica-family Xbow MDA100CA and MDA100CB sensor boards, which have +temperature and light sensors. It is found in +tos/sensorboards/mda100:
++./tos/sensorboards/mda100: +.sensor # Compiler configuration +ArbitratedPhotoDeviceP.nc # Light sensor support component +ArbitratedTempDeviceP.nc # Temperature sensor support component +DemoSensorC.nc # Override TinyOS's default sensor +PhotoC.nc # Light sensor HIL +PhotoImplP.nc # Light sensor support component +PhotoTempConfigC.nc # Shared support component +PhotoTempConfigP.nc # Shared support component +SharedAnalogDeviceC.nc # Shared support component +SharedAnalogDeviceP.nc # Shared support component +TempC.nc # Temperature Sensor HIL +ca/TempImplP.nc # Temperature sensor support component + # (MDA100CA board) +cb/TempImplP.nc # Temperature sensor support component + # (MDA100CB board) +mda100.h # Header file for mda100 ++
This sensor board provides only a HIL (PhotoC and TempC components), and overrides the +TinyOS demo sensor (DemoSensorC). The demo sensor is an alias for PhotoC.
+The two forms of the mda100 differ only by the wiring of the +temperature sensor. The user has to specify which form of the sensor +board is in use by providing a -I%T/sensorboards/mda100/ca or +-I%T/sensorboards/mda100/cb compiler option.
+This sensor board relies on a platform-provided MicaBusC component +that specifies how the mica-family sensor board bus is connected to +the microcontroller.
+