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Sample Driver Mask

The following is the block mask for the Diamond MM-32 Analog Input block.

If you were to create this mask as a new mask, you would:

1. Open the Mask Editor for the block.

2. Select the Parameters tab and click the Add button on the left three times.

   Three blank lines appear in the Dialog parameters section. Fill them in as follows, starting with the first line:

   • In the Prompt column, enter

     Channel configuration

     First channel number:

     Number of channels:

     Range

     Sample time:

     Base address (for example 0x300):

   • In the Variable column, enter the parameter names. Be sure that these names match the S-function parameters field of the S-Function block.

     configuration

     firstChan

     numChans

     range

     sampleTime

     base

   • In the Type column, select:

     popup

     edit

     edit

     popup

     edit

     edit

   • In the Evaluate and Tunable columns, ensure that the first five check boxes of Evaluate and all the check boxes for Tunable are selected.

   

3. Select the Initialization tab. The tab displays the dialog variables you entered in the Parameters tab.

4. In the Initialization code section, type

   phase = 2;
   [baseDec, maskDisplay, maskDescription] = 
   maddiamondmm32(phase, configuration, firstChan, 
   numChans, range, base);
   set_param(gcb, 'MaskDescription', maskDescription);
   set_param(gcb, 'MaskDisplay', maskDisplay);

   where maddiamondmm32 references the maddiamondmm32.m file for the driver.

   In this M-file, you should check the range values of the parameters. Checking the mask here will catch illegal values early in the build process.

   This example returns a string to display on the block with the variable port_label commands with which to label the input and output ports. The number and content of the port_label commands depend on the channel vector that the user enters in the mask.

5. Select the Documentation tab. This tab contains three fields, Mask type, Mask description, and Mask help.

   In the Mask type field, enter the type of driver. For example:

   addiamondmm32

   In the Mask description field, enter a description for the driver. For example:

   MM-32
   Diamond
   Analog Input

   In the Mask help field, if you are providing any online documentation to associate with the Help button, you can call that online documentation from this field. See Defining Mask Documentation in the Working with Block Masks chapter of Simulink User's Guide for details.

6. Click OK to save the mask.

After you create the block mask, you can define an InitFcn callback for the block. A model calls this callback at the start of model simulation.

1. Right-click the block and select Block Properties from the drop-down list.

2. Select the Callback tab from the dialog. From the list, select InitFcn. Enter M-code in the edit box.

   One convention is to use the same function that is used at mask initialization time (for example, maddiamondmm32.m), but with a single argument that indicates that this is being called at InitFcn time.

   maddiamondmm32(1)

   At InitFcn time, no variables in the mask exist yet. You cannot pass them into the InitFcn. However, in the function, you can get the string values using the get_param function. For example:

   function [baseDec, maskDisplay, maskDescription] = ...
           maddiamondmm32(phase, configuration, firstChan, numChans, range, base) %#ok
   
       vendorName   = 'Diamond';
       deviceName   = 'MM-32';
       description  = 'Analog Input';
       maskType     = 'addiamondmm32';
       
       if phase ~= 2  % assume InitFcn unless phase 2
           base = get_param( gcb, 'base' );
           blocks = find_system(bdroot, 'FollowLinks', 'on', ...
   				'LookUnderMasks', 'all', 'MaskType', maskType, 'base', base);
           if length(blocks) > 1
               error('xPCTarget:DiamondMM32:Block',...
                     'Only one Diamond Systems MM-32 A/D block per ...
   							physical board allowed in a model - each block of ...
   							this type must have a distinct ISA address.');
           end
           return
       end
   

When You Are Done

Interrupt Support

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