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This module describes the basics of the TI DSP/BIOS Task Module (TSK).


DSP/BIOS provides several different managers manage threads of execution. One of them is the Task Manager (TSK). This module explains the basics of TSK objects and use. This module only explains the use of static TSK objects which are set up using the configuration tool.


  • SPRU423 TMS320 DSP/BIOS Users Guide: Read the section on Tasks

Tsk module

Tasks are independent threads of code that conceptually run concurrently. The processor time is shared among the tasks. Each task has a priority which is used to determine which task gets processor time.

Each task has its own stack to store local variables, nesting function calls and for saving the task state when it is preempted. The stack size can be set individually for each task.

A task is always in one of four states

  • Running , which means the task is the one actually executing on the system’s processor;
  • Ready , which means the task is scheduled for execution subject to processor availability;
  • Blocked , which means the task cannot execute until a particular event occurs within the system; or
  • Terminated , which means the task is “terminated” and does not execute again.

Figure 1 shows a state transition diagram for a task. There is only one thread in the TSK_RUNNING state. When a task is in the TSK_RUNNING state all the other tasks in the TSK_READY state are at the same or lower priority. When a task of higher priority enters the TSK_READY state a preemption immediately occurs and the running task enters the TSK_READY state and the higher priority task enters the TSK_RUNNING state. Tasks can become blocked when a resource is unavailable or when some other event that causes blocking occurs. Semaphores are used to synchronize access to resources and can cause a task to block. When the resource becomes available the task enters the TSK_READY state.

State transition diagram for a task

To create a TSK object, open the configuration file, right click on Scheduling->TSK and select Insert TSK . You can right click on the object and select Properties to change its properties. Set the TSK priority on the General tab. Click on the Function tab and put the function name (preceded by an underscore) in for the function you want to handle the TSK. Figure 2 shows a view of the configuration file where the TSKs can be seen in their corresponding priority. Notice that the TSK_idle is priority 0 and it is reserved. This is the idle task.

When your program runs, the tasks with the same priority will get initialized in the order that they are shown in the configuration tool.

Configuration file showing TSKs and priorities

There are many functions in the TSK module. Some of the more commonly used ones are:

  • TSK_disable - Disable DSP/BIOS task scheduler
  • TSK_enable - Enable DSP/BIOS task scheduler
  • TSK_yield - Yield processor to equal priority task
  • TSK_sleep - Delay execution of the current task

As an example, suppose there are two task at the same priority as shown in the configuration file in Figure 3. To set up the threads of execution, change the Function properties to _funTSK0 for task TSK0 and _funTSK 1 for task TSK1 as shown in Figure 4.

Configuration tool showing two tasks at Priority 1

Function name for the Task

Then the main.c file will need two functions funTSK0 and funTSK1 as shown in the following listing.

#include<std.h>#include<log.h>#include<tsk.h>#include "tskcfg.h"Void main() {}Void funTSK0() {LOG_printf(&trace, "TSK0 Start"); TSK_yield();LOG_printf(&trace, "TSK0 Main"); TSK_yield();LOG_printf(&trace, "TSK0 Finish"); }Void funTSK1(){ LOG_printf(&trace, "TSK1 Start"); TSK_yield();LOG_printf(&trace, "TSK1 Main"); TSK_yield();LOG_printf(&trace, "TSK1 Finish"); }

When the program starts, the TSK0 runs first since it is the first on the list under Priority 1. It will print one statement and then yield to another task at the same priority, which will be TSK1. TSK1 will then begin its execution. The result of the whole run is:

TSK0 Start TSK1 StartTSK0 Main TSK1 MainTSK0 Finish TSK1 Finish

Viewing objects

Whe debugging a project it is important to see the characteristics of the components in your project. When using DSP/BIOS in CCS it is possible to view the DSP/BIOS objects and their properties using the RTSC Object Viewer (ROV). RTSC is Real Time Software Components which is a standard for developing software modules/libraries.

To view the DSP/BIOS v5.x objects and properties in the debug mode, select Tools->ROV . This will bring up a window that looks like the following figure.

RTSC Object Viewer

This figure shows the TSK module and the two tasks in the project. Notice the different properties that can be seen for each task.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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