3 keypad interface, 1 general, 2 connections – Matrix Orbital PK202-24-USB User Manual

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2.6.12 Cursor Right (254 77)

Moves the cursor one position to the right but does not erase any character that may be in that position.

Note that this command moves the text insertion point even if the cursor is turned off.

3 Keypad Interface

This chapter describes the keypad interface and associated commands in detail.

3.1 General

The display keypad interface processes the keypad row / column matrix into a serial data byte stream.

Aside from this processing, the keypad has no effect on the display. To send keystrokes to the display, they

must be routed through the controller.

3.2 Connections

Figure 13: Keypad Connector

The connector is not ’keyed’, so the keypad will probably plug in either of two ways. The display will

not be damaged by reversing the connector. However, the keypad will generate a different ASCII character

mapping for each position. If the connector has fewer than 10 pins it should be centered on pins 6 and 7 of

the connector.

Pins 1 through 6 are columns and Pins 7 through 10 are rows. The keypad is scanned wherever a key is

passed; there is no continuous key scan. This means that keypresses are dealt with immediately without any

appreciable latency. This also prevents electrical noise which is often caused by continuous key scans.

NOTE Please note that keypads may be laid out in a different pattern. If this is the case,

the user will need to interpret the key codes differently.

Matrix Orbital

PK202-24-USB

15

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