Appendix G Input/Output Device Commands - IBM 4840-563 System Reference Manual

Appendix G Input/Output device commands

This appendix lists the commands and their usage for the SurePOS 500 Series I/O devices.
VFD commands
This section describes the following VFD commands: v Emulation Mode Select v
Character Set Select v User Character Definition v Brightness Control v Alphanumeric
Message Scroll v Backspace v Horizontal Tab v Line Feed v Carriage Return v Test v
Display Position v Normal Display v Vertical Scroll v Cursor On v Cursor Off v Reset
Note: The command code format shown in the following topics is the hexadecimal
Emulation mode select (00) <NULL>
Purpose:
Character set select (02) <STX>
Note: This command is only effective in IBM Mode.
Purpose:
This example selects the US/European character set:
User character definition (03) <EXT>
Purpose:
Defines a custom character.
Logic Controls Emulation Mode
The byte that follows the command byte contains an ASCII character between X'20' and X'7F' of a keyboard
key to be redefined. This byte is followed by five bytes, which define the bit patterns of the user-defined
character. Logic Controls Emulation Mode only allows one keyboard key to be redefined. This means that
there is only one user-definable character in this mode. Once a key is redefined, any occurrence of that
character on the display will change to the user-defined character. If a new key is redefined, the previously
redefined key is restored to the original character in all places on the display and the newly redefined key will
SurePOS 500 Model XX3 Technical Reference, v 1.3
value followed by the ASCII representation of that value within brackets.
00 nn
Sets the specified emulation mode.
This example sets Logic Controls emulation mode:
00 00
02 nn
Selects the specified character set.
02 00
03 nn
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