Specifications

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13.1 Backlight Function
The BHT has a backlight function (LCD backlight and key backlight). Pressing the right-hand
trigger switch (M4 key) while holding down the Shift key activates or deactivates the backlight
function. The default length of backlight ON-time (ON-duration) is 3 seconds.
By using an
OUT statement, you can enable/disable either or both the LCD backlight and key
backlight. (Refer to Appendix D, "I/O Ports.")
By using a
KEY statement, you can select the backlight function on/off key instead of the com-
bination of the trigger switch and Shift key, as well as modifying the ON-duration of the back-
light. For details about the
KEY statement, refer to KEY in Chapter 14.
Setting 1 to port 6020h with the
OUT statement activates the backlight function and turns on
the backlight. If no key is pressed for the time length preset to port 6021h (default time: 5 sec-
onds), the backlight goes off but the backlight function remains activated.
Backlight OFF
The backlight function is
OFF when you turn on
the BHT.
If no key is pressed
for 3 seconds, the
backlight goes off.
Backlight ON
Backlight OFF
(The backlight function
remains ON.)
Press any key except for the
backlight function on/off key.
Press the right-hand
trigger switch while holding
down the Shift key.
Or, press the backlight
function on/off key specified
by statement.
Press the right-hand
trigger switch while holding
down the Shift key.
Or, press the backlight
function on/off key specified
by statement.
Press the right-hand
trigger switch while holding
down the Shift key.
Or, press the backlight
function on/off key specified
by statement.