VeriFone MX800 series Programmer's Manual page 53

With the callback function, the PIN entry process can control the audio and visual
aspects as each key press is detected, and its prototype is:
void callback(char value);
Table 6
Value Action
Lower nibble:
A numeric key was pressed. A PIN digit has been added to the
0x?1
internal PIN buffer. Application should display an <echo>
character.
BACKSPACE key was pressed. A PIN digit has been removed
0x?2
from the internal PIN buffer. Application should display a
<default> character (e.g. space, '-' or '_') in place of the last
<echo> character.
CLEAR key was pressed. All PIN digits have been removed from
0x?3
the internal PIN buffer. Application should replace all <echo>
characters with <default> characters.
Other key #1 was pressed. Pin Entry will be aborted as if the
0x?5
CANCEL key was pressed. The application can use this code to
define an option key such as a CREDIT button.
Other key #2 was pressed. Pin Entry will be aborted as if the
0x?6
CANCEL key was pressed. The application can use this code to
define an option key such as a CREDIT button.
Upper nibble:
Play "normal" sound
0x7?
Play "error" sound. This is sent when:
0xF?
•
•
•
Example 1: when a valid numeric entry is detected, the function will be called
once:
callback(0x71);
display <echo> character */
Example 2: when the backspace key is detected:
callback(0x72);
BACKSPACE was pressed*/
Example 3: when a key is pressed to clear the line when 3 inputs are entered:
callback(0x73);
CLEAR was pressed*/
BACKSPACE or CLEAR is pressed when there is no PIN digit
in the internal buffer.
A numeric key is pressed when there is already the maximum
number of PIN digits in the internal buffer.
ENTER is pressed when there is not the minimum number of
PIN digits in the internal buffer.
/* Tell the application to play normal sound and to
/* Tell the application to play normal sound and that
/* Tell the application to play normal sound and that
D
SetSecurePINDisplayParameters()
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