Technical Information

Application Development Manual | Waiting for key presses

Waiting for key presses

Function

Suspend the user application program, waiting for a key press.

Syntax

Detailed Description

This particular WAIT statement waits for port 0 bit 0 to go to 1, indicating that there is data in the keyboard buffer.

To wait until ENT, F1, or other specific key is pressed, use this WAIT statement to wait for a key press, read the key data with the INKEY$ function, and thus determine which key was pressed.

The following table gives the default key assignments.

Key Default key data
F1 A
F2 B
F3 C
F4 D
F5 E
F6 F
F7 G
F8 H
ENT Carriage return (0Dh)
BS Backspace (08h)
C Cancel (18h)

For further details on keys other than the above, refer to Appendix E "Key Number Assignment on the Keyboard" in the BHT-BASIC Programmer's Manual.

Examples
Wait until ENT key pressed
  private waitENT$
waitENT:
wait 0,&h01                    ' wait for key press
waitENT$ = inkey$              ' read key data for key pressed
if waitENT$ <> chr$(&h0D) then ' if key not ENT
goto waitENT                 ' wait for next key press
endif
print "ENT"
Wait until F1 or F2 key pressed
  private waitkey$
waitkey:
wait 0,&h01                    ' wait for key press
waitkey$ = inkey$              ' read key data for key pressed
select waitkey$
case "A":                    ' if F1 key
print "F1"                 ' display key name
case "B":                    ' if F2 key
print "F2"                 ' display key name
case else:                   ' if key not F1 or F2
goto waitkey               ' wait for next key press
end select

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