µC/OS-II, The Real-Time Kernel is a highly portable, ROMable, very scalable, preemptive real-time, multitasking kernel (RTOS) for microprocessors and microcontrollers. µC/OS-II can manage up to 255 tasks and provides the following services:
- Semaphores
- Mutual Exclusion Semaphores (to reduce priority inversions)
- Event Flags
- Message Mailboxes
- Message Queues
- Task Management (Create, Delete, Change Priority, Suspend/Resume etc.)
- Fixed Sized Memory Block management
- Time Management
- Timer Management
For more information about TCP/IP network stacks, file systems, GUI libraries and other software available for uC/OS-II go to:http://micrium.com/products/rtos/kernel/rtos.html
Getting Started Example Design
Description:
This application demonstrates the use of MicroC/OS-II message mailboxes,
and additionally, serves as a good starting point for designs using
MicroC/OS-II with Nios II. Message mailboxes are generally used to signify the
occurance of an event and/or for inter-task communication. MicroC/OS-II
message mailboxes are very similar to message queues, except
that they do not hold multiple elements like a queue. New mailbox message
postings will overwrite previous messages posted to the mailbox even if the
messages have not been read by any task.
The application has three tasks (task1, task2, task3) that post messages
to three different message mailboxes (mailbox1, mailbox2, mailbox3).
Upon receiving a message, the task increments the value of the message
and then passes the new value to the next task through a different
message mailbox.
Instructions:
Note: If you are on Nios II EDS v7.2 and prior then the installation directory already contains this example.
Follow the steps for Nios II EDS V8.0 and later:
- Download the zip file
- Copy the hardware example design for the developement kit you have from the Nios II EDS installation (C:\\\\altera\\\\<version number>\\\\nios2eds\\\\example\\\\<verilog or vhdl>) to your working directory.
- Extracts the contents of the zip file to the software application directory for teh hardware project in your working directory. e.g. \\\\<work dir>\\\\<hardware_design_name>\\\\software_examples\\\\app directory. For example, if you are using the standard verilog hardware design on the Nios II Development Kit, Cyclone II Edition, extract the zip file to /<work dir>\\\\niosII_cycloneII_2c35\\\\standard\\\\\\\\software_examples\\\\app
- Refer to the introduction to the Nios II Software Build tools chapter for instructions on building and running the example: http://www.altera.com/literature/hb/nios2/n2sw_nii52014.pdf
Hardware Boards:
- The supported Example Hardware Platforms:
Standard
Full Featured
Low Cost - Supported Development Boards
Nios Development Board, Stratix II Edition
Nios Development Board, Stratix Professional Edition
Nios Development Board, Stratix Edition
Nios Development Board, Cyclone Edition - System Library settings:
RTOS Type - MicroC/OS-II
Period System Timer - SYS_CLK_TIMER
Known Issues:
If this design is run on the ISS, terminal output will take several
minutes per iteration.
