Transcript Presentation Title Here

Getting started with IAR PowerPac for MSP430
Mats Pettersson, IAR Systems
• Fast…
• Everything can be found on www.iar.com
• Evaluation and kickstart versions free to download
• Demo after the PowerPoint slides
• Feedback and questions to [email protected]
July, 2008
1
Support
IAR Systems
IAR PowerPac for
MSP430
RTOS
and
File System
Tools
July, 2008
3
IAR Systems
• Founded in 1983 in Uppsala, Sweden
(Headquarter)
• About 140 employees
• Offices in the US (3), China, Japan, the UK,
Belgium, Germany, Brazil and Sweden
• 80.000 application developers
• Partner with 16 of the top semiconductor
companies
July, 2008
4
Support
IAR Systems
IAR PowerPac for
MSP430
RTOS
and
File System
Tools
July, 2008
5
• What is an RTOS?
Software that manages the time and other resources of a
microprocessor or microcontroller. It breaks down the
application into multiple tasks each handling one aspect of the
application.
It’s like having multiple CPUs!
• What is a File System ?
Software for storing and organizing data on storage devices.
Functions to create and handle files and directories in an
application.
RTOS
and
File System
July, 2008
6
Why use an RTOS ?
•
•
•
•
•
•
•
•
•
Ensure that high priority tasks run first
Deterministic response
Saves power!
Saves development time
Easy to structure/divide code between developers.
Correctness - easier to understand complex systems
Makes programming more efficient/better structured
Abstracts the hardware-dependence, porting easier
and much, much more…
RTOS
and
File System
July, 2008
7
Scheduling
The algorithms that determine which task to execute
Distinguish between tasks that are ready to be
executed and other tasks that are suspended
The task which is currently executing is referred to as
the active task
RTOS
and
File System
July, 2008
8
Tasks
Each task consist of:
• The program code, which usually resides in ROM
• A stack, residing in a RAM area that can be accessed by the
stack pointer
• A task control block (TCB), residing in RAM. The TCB is only
accessed by the RTOS
RTOS
and
File System
July, 2008
9
Communication between tasks
As tasks run in the same application, they sometimes
need to communicate with each other to:
• exchange data with other tasks
• synchronize with other tasks
• make sure that a resource is used by no more than one task at
a time
Can be achieved by:
• Global variables..... 
• RTOS communication mechanisms 
RTOS
and
File System
July, 2008
10
Communication mechanisms
Events
Mailboxes
• A buffer that is managed by
the real-time operating system
• Fixed message size
Semaphores
• Used for managing
resources by avoiding
conflicts caused by
simultaneous use of a
resource
• Resource semaphore
• Counting semaphore
Task events are
messages to a single,
specified recipient
Queues
• Similar to mailboxes, but
enable inter task
communication with larger
messages
• Messages of various sizes
RTOS
and
File System
July, 2008
11
Task oriented design
Benefits
• Clearer design
• Polling is avoided
• Adding a lower priority task will not affect the responsiveness
of the system to high priority tasks
• Code can be modularized, making things easier to maintain
and debug
• Saves power
RTOS
and
File System
July, 2008
12
File System features
Fail-safe operations
• The driver makes only atomic actions and takes the
responsibility that the data managed by the file system is
always valid.
• In case of a power loss or a power reset during a write
operation, it is always assured that only valid data is stored
in the flash.
• If the power loss interrupts the write operation, the old data
will be kept and the block will not be corrupted.
Wear leveling
• makes sure that the number of
erase cycles remains approximately
equal for each sector
July, 2008
RTOS
and
File System
13
Support
IAR Systems
IAR PowerPac for
MSP430
RTOS
and
File System
Tools
July, 2008
14
Complete suite of tools
visualSTATE
Idea
IAR
Embedded
Workbench
Verify,
Design Validate,
Implement
IAR
PowerPac
JTAG
debugger
Compile
Debug
IAR
Development
Kits
Deploy
RTOS & Middleware
Tools
July, 2008
15
Target
application
Support
IAR Systems
IAR PowerPac for
MSP430
RTOS
and
File System
Tools
July, 2008
16
IAR PowerPac for
MSP430
Why use a commercial RTOS
?
Proven code
Hard real time
Priority
controlled
Mulititasking
Costs
Shorter time
to market
Commercial RTOS?
Visualization
July, 2008
Documentation
17
TM for MSP430
IAR
PowerPac
IAR PowerPac for
MSP430
Fully featured real-time operating system
Additional
components
IAR PowerPac USB
IAR PowerPac Source
(RTOS + File System)
IAR PowerPac Base
High performance file system
Innovative business model similar to that
of IAR Embedded Workbench
Tight integration with IAR Embedded
Workbench
Easy to get started
(RTOS + File System)
Board support packages
July, 2008
18
IAR PowerPac for
MSP430
Operating system
Key features
Small memory footprint
(1.7 KByte for typical MSP430 implementation)
Pre-emptive multi-tasking
Round-robin scheduling
Up to 255 priorities
Unlimited number of tasks, semaphores, mailboxes
and software timers
Full interrupt support with nested interrupts
Very fast context switch times
Power Management
July, 2008
19
IAR PowerPac for
MSP430
RTOS performance
Memory usage
Kernel size (ROM)
1208 bytes
Kernel RAM usage
28 bytes
RAM usage per task
control block
18 bytes
RAM usage per resource
semaphore
8 bytes
RAM usage per counting
semaphore
4 bytes
RAM usage per mailbox
12 bytes
RAM usage per software
timer
12 bytes
RAM usage event
0 bytes
Min. stack-size per
July,task
2008
(RAM)
48 bytes
20
IAR PowerPac for
MSP430
RTOS performance
Timing
Context switch time
270 clock cycles (67.5 µs),
independent of number of
tasks
Interrupt latency time
max. 151 clock cycles (37.8
µs)
Kernel CPU usage/TICK
less than 1% of total
calculation time at 1000
Interrupts/second (1ms TICK)
Basic time unit (TICK)
typ. 1 ms, min. 100 µs (10 kHz
interrupt frequency)
July, 2008
21
IAR PowerPac for
MSP430
Support for MSP430
Low Power Modes
Task oriented design is very useful if you want to save
power
Peripherals can be switched of when not used
Wake up is possible through all enabled interrupts
Efficient OS causes minimum CPU overhead ->
maximizing idle time -> reducing power
consumption
July, 2008
22
IAR PowerPac for
MSP430
Support for MSP430
Low Power Modes
PowerPac RTOS fully supports all MSP430 low power
modes.
RTOS always brings CPU into lowest power mode
possible whenever CPU is idle
Peripheral clock requirements are taken into account
Lifts a lot of the burden for power management from
the programmer
July, 2008
23
IAR PowerPac for
MSP430
Support for MSP430
Low Power Modes
The idle task
• The idle task is only active when no other task has something to
do.
• Other tasks need to make operating systems calls to let the
system know when shared resources are or are not in use.
» OS_POWER_UsageDec(OS_UINT Level)
» OS_POWER_UsageInc(OS_UINT Level)
• The idle task will depending on which resources are used, enter
the lowest possible power mode.
July, 2008
24
IAR PowerPac for
MSP430
IAR PowerPac file system
Small footprint, e.g.
12 KByte ROM / 1.6 KByte RAM
MS-DOS/MS-Windows compatible
FAT12, FAT16 and FAT32 support
Multiple device driver support
Multiple media support
Caching functionality
Check disk functionality
Device drivers available for a number of
media types
July, 2008
25
IAR PowerPac for
MSP430
PowerPac File System API
layers
Application
- Contains functions in ANSI C stdio style,
FS_FOpen(), FS_FWrite() etc.
- Translates file operations to logical block
(sector) operations.
Storage API layer
- Optimized for applications which do not
require file system functionality.
- Allows sector read and write operations to
a storage medium
- A typical application: USB mass storage
device, data has to be stored on a
medium, but all file system functionality is
handled by the host PC.
July, 2008
PowerPac File System
File System API layer
API Layer
Storage API File System API
File System Layer
Storage Layer
Device Driver
Hardware Layer
26
IAR PowerPac for
MSP430
Integration with
IAR Embedded Workbench
Example projects available from the startup screen
Links to IAR PowerPac for MSP430 documentation in
the Help menu
Template projects within IDE for new library projects
RTOS aware debugging via C-SPY plug-in
Board Support packages
July, 2008
27
IAR PowerPac for
MSP430
IAR PowerPac for MSP430 evaluation version
Works with all EW430 product variants with the
following limitations:
• IAR PowerPac RTOS can either work without a time limit
with a maximum of three tasks or create more than three
tasks and work with a time limit of 15 minutes.
• IAR PowerPac File System can only handle one open file
at any given time
Time limited version will also be available
July, 2008
28
IAR PowerPac for
MSP430
IAR PowerPac business model
Principle
• Base product in object code format
Licensing model
• Seat license - per developer and CPU
• Full source code upgrade
• Group license (up to 20 developers)
• Site license (unlimited on the same site)
• No royalty fees
Result
• Low-risk licensing model
• A license can be used in unlimited number of projects and
products
• Affordable site license for unlimited number of developers
July, 2008
29
Support
IAR Systems
IAR PowerPac for
MSP430
RTOS
and
File System
Tools
July, 2008
30
Customer support
Support
Support and Update Agreement (SUA)
• Free software updates
• First class world-wide technical support by telephone, email and fax
• VIP Support contracts available
”My Pages” at www.iar.com
• Read about new product releases
• Download product updates
• Transfer licenses to co-workers
• Manage your contact information
July, 2008
31
Technical Resources
Support
www.iar.com
• Tecnical notes
• Application notes
• My Pages with latest product updates
Documentation
• User Guides for EW430 and PP430
• Reference Guides for all EW430 components
• Reference Guides for PP430 RTOS and FS.
July, 2008
32
Support
IAR Systems
IAR PowerPac for
MSP430 on
Demonstration
MSP-EXP430F5438
RTOS
and
File System
Tools
July, 2008
33
Summary
Our offering
• A tightly integrated RTOS, file system, and tools for
developing embedded applications
• Perfect compliment to IAR Embedded Workbench
• Innovative ”low-risk” price model
• Continuous ”add-ons” for more middleware’s
• Upgrade path
• Same license management system as IAR Embedded
Workbench
• Local support across the globe.
July, 2008
34
Thank you!
Please send feedback and questions to
[email protected]
July, 2008
35