Matrix Orbital VK204-25 Legacy - Manual (Page 40)

9.7 Set Auto Repeat Mode
Syntax Hexadecimal 0xFE 0x7E [mode]
Decimal 254 126 [mode]
ASCII 254 “~” [mode]
Parameters Parameter Length Description
mode 1 Auto Repeat Mode (0: Resend Key
, 1: Key Up/Down)
Description Two auto repeat modes are available and are set via the same command:
• Resend Key Mode: 0x00
• Key Up/Down Mode: 0x01
Resend Key Mode This mode is similar to the action of a keyboard on
a PC. In this mode, when a key is held down, the key code is
transmitted immediately followed by a 1/2 second delay. After
this delay, key codes will be sent via the RS-232 interface at a rate
of about 5 codes per second. This mode has no effect if polling or
if using the I
2 C interface.
Key Up/Down Mode This mode may be used when the typematic
parameters of the “Resend Key Code” mode are unacceptable or
if the unit is being operated in polled mode. The host system
detects the press of a key and simulates an auto repeat inside the
host system until the key release is detected. In this mode, when a
key is held down, the key code is transmitted immediately and no
other codes will be sent until the key is released. On the release of
the key, the key release code transmitted will be a value equal to
the key down code plus 20 hex.
Remembered Yes
Examples When the key code associated with key ’P’ (0x50) is pressed, the release
code is ’p’ (0x70). In RS-232 polled mode or via the I
2 C, the “Key
Down / Key Up” codes are used; however, the user should be careful of
timing details. If the poll rate is slower than the simulated auto-repeat it
is possible that polling for a key up code will be delayed long enough
for an unwanted key repeat to be generated.
9.8 Auto Repeat Mode Off
Syntax Hexadecimal 0xFE 0x60
Decimal 254 96
ASCII 254 “‘”
Matrix Orbital VK204-25-USB 36