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5-8
ChCharacter Input Methods
Programmer’s Manual
Personal Portable System Manager
Programmer’s Manual
5-5
5.2.1
The Input Pad Mechanism
The user writes a character within an input box to input it into the system. The
system proceeds to recognize a character when the user starts writing in a
different box, or when a predefined time has passed since the user lifts the pen,
whichever occurs first. The characters are recognized in the order they are
entered, independent of the box location. The application must define its own
mechanism to determine when character input is finished and close the input pad
(e.g. the user clicks on a close input pad button created by the application).
The input pad is a subtask. Once it is opened, handwriting recognition interrupt
messages, IRPT_HWR, are generated to its main task when characters are being
recognized. Each individual recognized character generates an individual
IRPT_HWR interrupt message. Through this interrupt message, the system
returns the recognized character candidates to the main task which opened the
input pad. (Refer to Section 15.1.8 - IRPT_HWR).
Only ONE instance of the input pad is supported per main task(ie. shared among
parent and sub-tasks). If the user opened an input pad in one of the tasks, an
attempt to open the input pad in any other task in its parent/sub-tasks chain would
fail. If the user switches to another task chain while an input pad has been opened
in the current task. The handwriting recognition engine is reset and the input box
area is cleaned if the areaClean(see below)
5.2.2
Starting Handwriting Character Input
STATUS
OpenInputPad
U16 areaSize)
,
An application can open the input pad anywhere within the panning screen. The
User’s handwriting
Application
PPSM
Input Pad
Open/Close
Character candidates
and error code
Figure 5-4 Data flow of Handwriting Recognition Input
F
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