Select and connect digital output lines or channels
The Digital Output block allows you to select and connect specific digital lines or channels to your Simulink® model. After you have added a Digital Output block to your model, you can enter the parameters for its I/O driver. The following procedure uses the HUMUSOFT® AD512 I/O board as an example.
Enter a value representing how frequently you want the block to execute and interact with the I/O hardware. The block will also synchronize your model with the real-time clock at this sample rate.
Enter the number of timer ticks that your model can lag behind the real-time kernel. When the model lags by more than this number, the block reports an error and simulation stops. Otherwise, simulation continues even if some ticks are missed.
Select this check box to display the current number of missed ticks as a block output.
Select this check box to grant other programs more CPU time while the kernel waits for a response from the hardware.
Enter a channel vector that selects the digital output channels you are using on this board. The vector can be any valid MATLAB® vector form. For example, to select the eight digital output channels on the AD512 board, enter
[1,2,3,4,5,6,7,8] or [1:8]
If you want to use the first four digital output lines, enter
If you have one 8-bit digital channel, enter . If you have two 8-bit digital channels, enter [1 9], and from the Channel mode list, choose Byte.
Bit — Expects a value of 0 or 1.
Byte — Expects a value of 0 to 255 that is converted to one digital channel of eight digital lines.
Enter the initial values for each digital output line or channel you entered in the Output channels box. For example, if you entered [1,2,3,4] in the Output channels box, and you want initial values of 0 and 1, enter
If you choose Byte from the Channel mode list, enter a value between 0 and 255 for each digital output channel. For example, for one byte (8 digital lines) with an initial value of 25, enter . For two bytes (16 digital lines) with initial values of 25 and 50, enter [25 50].
If you choose Byte from the Channel mode list, enter a value between 0 and 255 for each digital output channel.