PK202-25 Matrix Orbital, PK202-25 Datasheet - Page 26

• Manufacturer Part Number: PK202-25
• Description: LCD Character Display Modules Black Background Yel/Grn Text
• Manufacturer: Matrix Orbital
• Series: PK202-25r

Specifications of PK202-25

• Character Count X Line: 20 x 2
• Module Size (w X H X T): 116 mm x 37 mm x 25.73 mm
• Background Color: Black
• Backlight Type: LED Yellow / Green
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.5.3 Auto transmit keypresses on (254 65) (R)
command. This is the default mode on power up.
4.5.4 Auto transmit keypresses off (254 79) (R)
keypad command. Issuing this command places the unit in polled mode.
4.5.5 Clear key buffer (254 69)
changes the menu context, any following key presses may be inaccurate and can be cleared out of the buffer
between menu changes to prevent jumping around the menu tree. It may also be used to, in effect, reset the
keypad in case the host application resets for whatever reason.
4.5.6 Poll keypad (254 38)
set up to receive the key codes. When the display receives this command it will immediately return any
unbuffered keypresses which may have not been read already. If there is more than one keypress buffered,
then the high order bit (MSB) of this returned keycode will be set (1). If this is the only buffered keypress,
then the MSB will be reset (0). If there are no buffered keypresses, then the returned code will be 0x00.
Please note to make use of this command the "Auto transmit keypress" mode should be off.
4.5.7 Set debounce time (254 85 [time]) (R)
piezo switches will ‘bounce’ for a varying time, depending on their physical characteristics. The default
debounce time for the module is about 52 ms, which is adequate for most membrane keypads.
5 Bar Graphs and Special Characters
define up to eight special characters.
ters, and big numbers. Since the same 8 characters are used for each function, the functions may not be used
simultaneously. The bottom row of pixels is normally reserved for the underline cursor. The characters may
Matrix Orbital
In this mode, all keypresses are sent immediately to the host system without the use of the poll keypad
In this mode, up to 10 keypresses are buffered until the unit is polled by the host system via the poll
This command clears any unread keypresses. In a menuing application, if the user presses a key which
This command returns any unbuffered keypresses via the RS-232 interface. The host system must be
[time] is in increments of 6.554 milliseconds.
This command sets the time between key press and key read. All key types with the exception of latched
The display includes the ability to draw bar graphs (either horizontal or vertical) and allows users to
Eight characters (ASCII values 0x00 to 0x07) are set aside for use with bar graphs, user defined charac-
PK202-25
22