Casio IT-2000D User Manual
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About the buffer clear
Consider the appropriate timing to clear the buffer. If the buffer clear command is issued after the
down coordinates are acquired, acquisition of the up coordinates is hampered. Or, if the buffer
clear command is issued after the "data present" report is received as a result of executing the key
scanning function without performing data input, the keycode for which the key scanning
function returned the "data present" reply will not be cleared. Also note that on a scanning code,
such as a delete code or insert code, that has a first byte of 00h, the second code cannot be
cleared, if the first code has already been acquired.
About the acceptance timing of keycodes
With the keypad of this system the keycode acceptance and video-reversing processes for the
touched key are triggered when key scanning and key input are started. Therefore, if a program
has an extremely long interval between key inputs, a time lag from the actual operation may
occur, resulting in the key area being reversed after the pen is removed. Also, if the touch panel
is touched after one ten key has been pressed, the keycode of the touch panel key will be
returned first in the subsequent key input process. This occurs because the keypad driver first
processes touch panel input and then processes ten key input. The above facts require the
program to be created in such a way that the interval between key inputs is not extremely long.
Input of a ten key while the touch panel is being touched
If a ten key is pressed while the touch panel is being touched, the corresponding key code will
be logged during the interval between when the down coordinates are acquired and when the up
coordinates are acquired.
About the up coordinates
The coordinates to be returned in the up status are the same as those that were last returned in the
run status.