Introduction
It is possible to display ASCII data by simply using the ASCII display object. ASCII data is stored in Mitsubishi PLC data registers as bytes, thus two ASCII characters can be saved in one data register. Or to put it another way, it is possible to display 10 ASCII characters in 5 consecutive data registers.The ASCII input object works in exactly the same ways as the ASCII display object but it allows the user to input ASCII data. The only additional item that has to be setup to enable the ASCII input object to work correctly is an ASCII input keyboard.
Design Considerations
To allow ASCII input, an ASCII keyboard must be setup (or created), saved into a screen and then the screen must be linked to each ASCII input object and/or set for the whole project. ASCII keyboards must either be created by hand or predefined keyboards can be used.There is a large array of predefined keyboards available within GT Designer libraries. These keyboards can aslo be modified by ungrouping the objects and amending them as required. The example below shows the “ASCII_B” keyboard that can be found in the “AV ASCII Keyset”.
To be able to use a keyboard with an ASCII input object the keyboard should be saved into Window Screen. The simplest way to do this is to create a new Window Screen, paste one of the library keyboards into it, and then set the screen size to match the size of the keyboard.
NOTE: the keyboard can also be resized and modified if needed.
There are two different ways of linking a keyboard screen to an ASCII input object. These are globally for the whole project or locally for each screen.
To setup a global ASCII input keyboard and ASCII Key Sheet must be configured in the System Settings / Environment Settings / Key Window setting area as shown below. In this example Window Screen 1 has been used and this contains the keyboard. The specific setting is Window Screen No for ASCII.
Further Information
For further information please refer to the GOT1000 screen design manual.
