# Lock _Block one physical input by class_ [`LOCK`](/native/commands/lock.md#lock) stops the physical device from driving one input while leaving everything else alone. It's generic over the input class: a relative axis, a mouse button, a keyboard key, or a media usage, plus a blanket lock for a whole class. Host [injection](/native/injection.md) still drives a locked input, so a script can take one over; it's [fire-and-forget](/native/injection.md#fire-and-forget). ## LOCK _Lock or unlock a physical input_ `LOCK` picks a `class`, an `id` within it, and a `direction`, then either blocks it or clears the block. A momentary usage shares [`INJECT`](/native/commands/inject.md#inject)'s `(class, id)` space, so a button locks exactly like a key. [Opcode](/native/frame.md#opcodes) `0x0A`. ```text LOCK 0x0A · payload 5 bytes ``` _Fire-and-forget_ #### PAYLOAD | Offset | Field | Type | Notes | | --- | --- | --- | --- | | 0 | `class` | `u8` | the input class (see below) | | 1 | `id` | `u16` | which input within the class, little-endian; `0xFFFF` = the whole class | | 3 | `direction` | `u8` | which sign or which edge (see below) | | 4 | `state` | `u8` | `1` = lock, `0` = unlock | #### CLASSES | Class | Value | `id` is | | --- | --- | --- | | button | `0` | a [button id](/native/commands/usage.md#buttons) (0=Left .. 4=Side2) | | key | `1` | a [HID keyboard usage](/native/commands/usage.md#keycodes) (0xE0-0xE7 = modifier) | | media | `2` | a 16-bit [Consumer usage](/native/commands/usage.md#consumer) | | axis | `3` | 0=X, 1=Y, 2=wheel (the sign is the direction) | Classes `0`\-`2` mirror [`INJECT`](/native/commands/inject.md#inject). An `id` of `0xFFFF` is a blanket: it locks every usage in that class in one command (every button, every key, or every media usage). #### DIRECTION What `direction` means depends on the input. For an axis it's a sign, so you can block scrolling up but not down. For a button, key, or media usage it's an edge, so you can block the press but not the release. | Direction | Value | Axis | Button / key / media | | --- | --- | --- | --- | | both | `0` | Both signs. | Press and release. | | positive | `1` | Positive sign only (`+`). | Press only (`0 to 1`). | | negative | `2` | Negative sign only (`-`). | Release only (`1 to 0`). | #### PHYSICAL ONLY A lock blocks the physical device and nothing else. Host [injection](/native/injection.md) still reaches a locked input, so a [`MOVE`](/native/commands/move.md#move) moves a locked axis and an [`INJECT`](/native/commands/inject.md#inject) drives a locked button or key. Lock an input the user shouldn't touch, then drive it yourself. #### A LOCK CLEARS ON ``` unlock you send the matching unlock (state = 0) silence ~1 s with no control-PC frame (same net as injection) RESET a RESET command link loss the inter-chip link drops ``` > **Warning** > > A lock isn't permanent. It auto-clears on the same safety net as injection, so hold it with a keepalive if the user has to stay locked out. #### EFFECT Locks are PC-owned and never visible to the game PC. [`QUERY(LOCKS)`](/native/commands/requests.md#locks) reads the active set across every class; the HEALTH [`LOCK_ON`](/native/commands/requests.md#health) bit is set while any lock, of any class, is active. Library bindings: [`lock`](/library/lock.md#lock) / [`unlock`](/library/lock.md#unlock), and [`lock_all`](/library/lock.md#lock-all) / [`unlock_all`](/library/lock.md#lock-all) for a blanket. #### EXAMPLE Lock the wheel's negative (scroll-down) sign: `class = 3` (axis), `id = 2` (wheel), `direction = 2`, `state = 1`: ``` +--------+--------+--------+--------+--------+--------+--------+--------+--------+ | A5 | 0A | 00 | 05 00 | 03 | 02 00 | 02 | 01 | lo hi | +--------+--------+--------+--------+--------+--------+--------+--------+--------+ | SOF | TYPE | SEQ | LEN | class | id | dir | state | CRC16 | +--------+--------+--------+--------+--------+--------+--------+--------+--------+ ```