Practical Tips for Using the Boto Touch Screen

Today I am going to share a very practical touch screen technique that displays all IO statuses on one touch screen page. Without further ado, let’s first look at the effect demonstration.

Video Demonstration

In the video, you can see that I only used one touch screen page, but multiple IO statuses are displayed. How is this achieved? Let me introduce it one by one.

First, let me introduce the variables used and associated with the touch screen, as shown in Figure 1.

In Figure 1, the left side shows 8 input signals, and the right side shows 8 output signals. The IO statuses are associated with the variables “HMI_DATA_Input Status Display” and “HMI_DATA_Output Status Display,” with their attributes shown in Figure 2.

In Figure 2, it is important to note that the “Type” is selected as a single bit, with the serial number ranging from 0 to 7 for selection, distinguishing the corresponding inputs. The output status display follows the same logic.

For the display of input and output names, a text category method is used. When the values of different variable names on different pages are different, different names are displayed, as shown in Figures 3 and 4.

In Figure 3, different values in the text list correspond to a name. In Figure 4, the names of input variables are associated with the text list. It should be noted that when the process values of input variables are different, the first is associated with “HMI_DATA_Display Text 0,” the second with “HMI_DATA_Display Text 1,” and so on. The same logic applies to the names of output variables.

The touch screen page status displays the current page and total pages, as well as the previous and next page associated variables, as shown in Figure 5.

After understanding the touch screen part, let’s introduce the PLC program. The variables in the PLC program include IO variables and program variables.

One processing for IO variables is to map the corresponding bytes into an array. The mapping part is omitted here, and the completed IO table is shown in Figure 6.

The program variables are shown in Figure 7:

In this program, both the previous page and the next page generate a signal, triggering different actions on different pages. On the first page, when the “Previous Page” button is pressed, it switches to the last page (i.e., page 5), and the displayed text page is the current page plus the corresponding value; when the “Next Page” button is pressed, the page increments by one, and the displayed text changes.

On the second and second-to-last pages (i.e., page 4), when the “Previous Page” button is pressed, the page number decreases by one; when the “Next Page” button is pressed, the page number increases by one, and the displayed text changes. On the last page, when the “Previous Page” button is pressed, the page number decreases by one, and the displayed text changes; when the “Next Page” button is pressed, it returns to the first page, and the displayed text changes. The program is shown in Figures 8, 9, and 10.

That concludes the content of this article. This method can not only be used for displaying IO statuses but also applies to the processing of multiple devices at multiple workstations. If you have more application tips for touch screens, feel free to leave a message for discussion.

Source: Technical Training Network, Author: Technical Training – Liu Chen, Reproduction without authorization is prohibited!