1. |
GP displays B1. |
At that time, the currently displayed screen number, [1] is stored in +0 of the system data area. |
2. |
Write the change destination screen number, [2] in +8 of the system data area from PLC side. |
3. |
GP displays B2. |
4. |
The screen is changed to B3 via a touch switch (a special SW etc.) of GP. |
[3] is stored in +0 of the system data area. |
*In this case, a screen number is not written in +8 of the system data area. +8 is still
[2]. |
5. |
Write [2] in +8 of the system data area. |
Since [2] has already been in +8 of the system data area, screens don’t change. |
*GP is watching changes of data and [2]->[2] means no change. |