How to change the number of input/output-terminals based on mask parameter

I’m now writing a custom driver for Simulink Real-time and have a question about how to change the number of input/output-terminals. I want to change the number of the terminals by setting the mask parameter “channel” like pre-installed drivers, e.g. MM-32 Diamond Analog Input or PCI-6621 National Instr. Analog Input.

I started to write the driver using “xpcdrivertool” and added initialization function (below) using these pre-installed drivers as examples.

function [maskdisplay]  = init(channel)

maskdisplay = sprintf( 'disp(''Interface Baord'');' );
for i=1:length(channel)
    maskdisplay = sprintf('%s port_label(''output'', %d, ''%d'');', maskdisplay, i, channel(i) );
end

In the mask editor of the driver block, I added ‘channel’ parameter and wrote an initialization command as follows.

[maskDisplay] = init(channel);
set_param(gcb, 'MaskDisplay', maskDisplay);

Also, I’m changing the number of terminals in the initialization function in C code as follows.

if (!ssSetNumOutputPorts(S, number_of_channels)) return;
for (i = 0; i <  number_of_channels; i++) {
 ssSetOutputPortWidth(S, i, 1);
}

However, the number of terminals does not change in the block diagram. Can someone please help me out?

Answer 1

[Shruti Sapre]

Hi Teppei,

The following link could help you in resolving this issue:

http://www.mathworks.com/matlabcentral/answers/30433-dynamically-change-the-number-of-ports-of-a-block

The “xpcdrivertool” seems to be from MATLAB Central, so it might also help to contact the author directly.

Hope this helps!

-Shruti

[Teppei Tsujita]

Hi Shruti,

I appreciate your help. The link helped me in finding my mistake. I did not pass the parameter “channel” to S-Function by specifying “S-Function parameters:” in Function Block Parameters Dialogue. I would like to attach my simplified code for those who have the same question.

Teppei