Screen Control Characters

The following variables hold the screen control characters. These can be used by the user as required. These control characters are

 REV.ON$

This variable holds the code that equates to REVERSE VIDEO ON. It is intended that this variable holds the special effects code so that anything after REV.ON$ is printed will be displayed in reverse video.

 REV.OFF$

This variable holds the code that equates to REVERSE VIDEO OFF. It is intended that this variable holds the special effects code that will 'turn off' any reverse video printing.

 CLEAR.EOL$

This variable holds the code that equates to CLEAR TO END OF LINE. It is intended that this variable holds the special effects code that will result in clearing down the details on the screen for the line on which the variable is printed.

 CLEAR.EOS$

This variable holds the code that equates to CLEAR TO END OF SCREEN. It is intended that this variable holds the special effects code that will result in clearing down the details from the position on the screen where the variable is printed, to the end of the screen.

 EPOS$

This variable holds the code that equates to ERROR MESSAGE POSITION It is intended that printing this variable will result in the bottom line of the screen being cleared of detail and the cursor positioning itself at the beginning of the bottom line of the screen. This variable will normally be used in conjunction with REV.ON$ and REV.OFF$ for printing error messages.

 R.EFFECTS$

This variable holds the code pairs that give rise to the user defined screen effects. These effects will be set up immediately after the call to the PARADYME routine PD.EFFECTS. Each attribute in this record will contain 2 values. The first value will contain the string to turn the effect on and the second value will hold the string to turn the effect off. Note that PARADYME will set these effects up as separate variables and consequently it is not expected that the user will directly access the R.EFFECTS$ variable.

All the above variables EXCEPT R.EFFECTS$ are passed to the PARADYME program via the standard PARADYME COMMON declaration.

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