DECLFKC—Local Function Key Control
This control function lets you select the action performed by some of the local function keys on the top row of the keyboard:
| Pk | Function | VT Keyboard | Enhanced PC Keyboard |
|---|---|---|---|
| 1 | Hold | F1 | Scroll Lock |
| 2 | F2 | Print Screen | |
| 3 | Set-Up | F3 | Caps Lock/Print Screen |
You can have the key perform its local function, send a function key sequence to the host, or do nothing.
This control function is useful for:
- Simplifying the keyboard for novice users
- Disabling features that are not compatible with the application, such as local printing
Format
| CSI 9/11 |
Pk1 3/n |
; 3/11 |
Pf1 3/n |
... ... |
Pkn 3/n |
; 3/11 |
Pfn 3/n |
* 2/10 |
} 7/13 |
Parameters
Pkn
is a number from 0 to 4 that corresponds to the local function key affected (F1 to
F4). A Pkn value of 0 means that all four keys (F1 through F4) are affected.
Pfn
controls the action of the local function key specified by the corresponding Pkn
value.
| Pfn | Meaning | VT Mode | PCTerm Mode |
|---|---|---|---|
| 0 | Selects the default function of the key. | Local print | Scan code |
| 1 | The key performs its local function either shifted, unshifted, or with the Ctrl key. | Local Print | |
| 2 | The unshifted key sends its function key sequence to the host. The key sends nothing when pressed with Shift or Ctrl. | Function Key | Scan Code |
| 3 | The key is disabled. | Disabled | Does not exist |
Description
DECLFKC can accept any number of parameter pairs. The terminal executes the parameters in the order in which it receives them.
Note on DECLFKC
Applications cannot disable the F5 (Break) key using this command. This restriction is required for secure systems, which ensures that the operator has control of the communication line.