Matrix Orbital LK204-7T-1U - Manual (Page 26)

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6.6 Keypad
6.1 Auto Transmit
Key Presses On Dec
Hex
ASCII 254 65
FE 41
■ A
v5.0
Key presses are automatically sent to the host when received by the display. Default is Auto Transmit on.
6.2 Auto Transmit
Key Presses Off Dec
Hex
ASCII 254 79
FE 4F
■ O
v5.0
Key presses are held in the 10 key buffer to be polled by the host using the Poll Key Press command. Use this
mode for I2C transactions. Default is Auto Transmit on.
6.3 Poll Key
Press Dec
Hex
ASCII 254 38
FE 26
■ &
v5.0
Reads the last unread key press from the 10 key display buffer. If another key is stored in the buffer the MSB will
be 1, the MSB will be 0 when the last key press is read. If there are no stored key presses a value of 0 will be
returned. Auto transmit key presses must be turned off for this command to be successful.
Response Byte Value of key pressed (MSb determines additional keys to be read).
6.4 Clear Key
Buffer Dec
Hex
ASCII 254 69
FE 45
■ E
v5.0
Clears all key presses from the key buffer.
6.5 Set Debounce
Time Dec
Hex
ASCII 254 85
FE 55
■ U
Time
Time
Time v5.0
Sets the time between a key press and a key read by the display. Most switches will bounce when pressed; the
debounce time allows the switch to settle for an accurate read. Default is 8 representing approximately 52ms.
Time Byte Debounce increment (debounce time = Time * 6.554ms).
6.6 Set Auto
Repeat Mode Dec
Hex
ASCII 254 126
FE 7E
■
DEL
Mode
Mode
Mode v5.0
Sets key press repeat mode to typematic or hold. In typematic mode if a key press is held, the key value is
transmitted immediately, then 5 times a second after a 1 second delay. In hold mode, the key down value is
transmitted once when pressed, and then the key up value is sent when the key is released. Default is typematic.
Mode Byte 1 for hold mode or 0 for typematic.