A.1.1.2 System Data Area (Direct Access Method)

This shows the contents of write data in each address of the System Data Area.

When Communicating with Device/PLC with Addresses that are 16 Bits or 32 Bits Long

1 Address Communicating with a 8-bit Device/PLC

Details About Each Address - System Data Area

The following example describes one address communicating with a 16-bit device/PLC.

• Current Screen Number

Stores the screen number that currently displays on the display unit.

• Error Status

When an error occurs in the display unit, the corresponding bit turns ON. After the bit turns ON and the power turns OFF, the status is maintained until the GP changes from offline mode back to active mode.

• Clock Data (Current)

Stored as BCD. [Year] is the 2 digits of the year, [Month] is 2 digits from 01 to 12, [Day] is 2 digits from 01 to 31, [Time] is 2 digits for the hours from 00 to 23, and 2 digits for the minutes from 00 to 59 for a total of 4 digits.

• Status

Monitor only the necessary bits. Do not turn reserved bits ON/OFF because they are sometimes used for display unit system maintenance.
 

*1 Even if you use GP-Viewer EX to operate the Data Display part, the bit does not change.

• Change-To Screen

Set the Change-to Screen Number. The setup range differs depending on the [Data Type of Display Screen Numbers] option, available from the [System Settings], [Display Unit] link, in the [Display] tab's [Screen Settings] area.

Data type is Bin: 1...9999

Data type is BCD: 1...7999

To change screens from both the display unit and the device/PLC, from [System Settings] click [Display Unit], and in the [Display] tab select the [Reflect in Device/PLC] check box. When the [Reflect in Device/PLC] check box is cleared, screen change using LS0008 is not reflected to the mapped device/PLC's System Data Area [Change-To Screen] address. As a result, screen changes may not be available from the device/PLC. (Unable to return to the screen before switching)
If you are not setting the [Reflect in Device/PLC] option, design the system to clear the change screen number to zero after screens are changed.

There is a method to change screens by force when you cannot change screens from the device/PLC side.
Turn ON the top bit (forced screen change bit) in the mapped device/PLC's System Data Area [Change-To Screen] address, and use the other bits to define the change to screen number. (In other words, enter the screen number you want to display plus 8000(h) in the address.) While the force screen change bit is ON, you cannot use touch operations to change screens. However, you can use the system variable #H_ChangeScreenNo to change screens.

• Screen Display ON/OFF

Shows the screen when the value is "0000h" and hides the screen when the value is "FFFFh". Do not use any values except "0000h" or "FFFFh". If you touch the screen while the screen is hidden ("FFFFh" is set), although touch operations such as switches do not operate, the screen reappears ("0000h" is set).

• Clock Data (Current Value)

Set as BCD. [Year] is the 2 digits of the year, [Month] is 2 digits from 01 to 12, [Day] is 2 digits from 01 to 31, [Time] is 2 digits for the hours from 00 to 23, and 2 digits for the minutes from 00 to 59 for a total of 4 digits. The defined clock data is written by switching the data write flag (LS0010, bit 15) from OFF to ON, or from ON to OFF.

For example, 2005, October 19, 21:57

1. When data in the current Word Address "+10" is "0000"
   Month→Write "0010" to Word Address "+11”
   Day→Write "0019" to Word Address "+12”
   Time→Write "2157" to Word Address "+13"

2. When you write "8005" to word address +10, bit 15 of address +10 turns ON, and clock data is written. For "8005," bit 15 is turned ON by the "8000" portion, while the "Year" is set with "05". (If bit 15 of word address +10 is already ON, write "0005". Bit 15 turns OFF, and the clock data is written.)

• Control

*1 The combination of settings to control the buzzer is as follows.

• Window Control

Controls the window display. 
12.7.2 Window - Word Action / Basic

• Window Number

Stores the Global Window's registration number selected indirectly: 1 to 2000 (BIN/BCD)

• Window Display Position

Stores the Global Window's top-left display position, selected indirectly. The data type is BIN or BCD.