Matrix Orbital PK202-25 - Manual (Page 25)

4.5 Keypad Commands
Some commands, marked with an “R”, may be "Remembered" to set new defaults that will be in effect
each time the unit is powered on. When “remeber” is set / turned on, these commands are automatically
remembered to take effect each time the unit is powered on, therefore there is no need to send the save
function.
4.5.1 Auto repeat mode on (254 126 [mode]) (R)
[mode] = 0x00 gives Resend Key Code mode
[mode] = 0x01 gives Key Down / Key Up Code mode
1. Resend Key Code: 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.
2. Key Down / Key Up Codes: 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. For example, 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 interface,
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.
Figure 22: Poll Timing
4.5.2 Auto repeat mode off (254 96) (R)
This command turns off auto repeat mode.
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