rebuffer_delay

Number of samples of delay introduced by buffering and unbuffering operations

Syntax

d = rebuffer_delay(f,n,v)
d = rebuffer_delay(f,n,v,'mode')


Description

d = rebuffer_delay(f,n,v) returns the delay, in samples, introduced by the Buffer or Unbuffer block in multitasking operations.

d = rebuffer_delay(f,n,v,'mode') returns the delay, in samples, introduced by the Buffer or Unbuffer block in the specified tasking mode.

Input Arguments

f	Frame size of the input to the Buffer or Unbuffer block.
n	Size of the output buffer. Specify one of the following: The value of the Output buffer size parameter, if you are computing the delay introduced by a Buffer block. 1, if you are computing the delay introduced by an Unbuffer block.
v	Amount of buffer overlap. Specify one of the following: The value of the Buffer overlap parameter, if you are computing the delay introduced by a Buffer block. 0, if you are computing the delay introduced by an Unbuffer block.
'mode'	The tasking mode of the model. Specify one of the following options: 'singletasking' 'multitasking' Default: 'multitasking'

Examples

Compute the delay introduced by a Buffer block in a multitasking model:

1. Open a model containing a Buffer block. For this example, open the ex_buffer_tut4 model by typing ex_buffer_tut4 at the MATLAB^® command line.

2. Double-click the Buffer block to open the block mask. Verify that you have the following settings:

   • Output buffer size = 3

   • Buffer overlap = 1

   • Initial conditions = 0

   Based on these settings, two of the required inputs to the rebuffer_delay function are as follows:

   • n = 3

   • v = 1

3. To determine the frame size of the input signal to the Buffer block, open the Signal From Workspace block mask. Verify that you have the following settings:

   • Signal = sp_examples_src

   • Sample time = 1

   • Samples per frame = 4

   Because Samples per frame = 4, you know the f input to the rebuffer_delay function is 4.

4. After you verify the values of all the inputs to the rebuffer_delay function, determine the delay that the Buffer block introduces in this multitasking model. To do so, type the following at the MATLAB command line:

   d = rebuffer_delay(4,3,1)
   
   d =
        8
   

Compute the delay introduced by an Unbuffer block in a multitasking model:

1. Open a model containing an Unbuffer block. For this example, open the ex_unbuffer_ref1 model by typing ex_unbuffer_ref1 at the MATLAB command line.

2. To determine the frame size of the input to the Buffer block, open the Signal From Workspace block mask by double-clicking the block in your model. Verify that you have the following settings:

   • Signal = sp_examples_src

   • Sample time = 1

   • Samples per frame = 3

   Because Samples per frame = 3, you know the f input to the rebuffer_delay function is 3.

3. Use the rebuffer_delay function to determine the amount of delay that the Unbuffer block introduces in this multitasking model. To compute the delay introduced by the Unbuffer block, use f = 3, n = 1 and v = 0.

   d = rebuffer_delay(3,1,0)
   
   d =
        3
   

More About

Multitasking

When you run a model in MultiTasking mode, Simulink^® processes groups of blocks with the same execution priority through each stage of simulation based on task priority. Multitasking mode helps to create valid models of real-world multitasking systems, where sections of your model represent concurrent tasks. The Treat each discrete rate as a separate task parameter on the Solver (Simulink) pane of the Configuration Parameters dialog box controls this setting.

Singletasking

When you run a model in SingleTasking mode, Simulink processes all blocks through each stage of simulation together. The Treat each discrete rate as a separate task parameter on the Solver (Simulink) pane of the Configuration Parameters dialog box controls this setting.