What would the syntax of serial command that triggered the AUX1 with STATE of HIGH look like?

I am trying to trigger a camera shutter module that needs a HIGH.



Here is the documentation but does not show the the syntax.

CMD_TRIGGER_PIN - Trigger pin
PIN_ID 1u Triggers pin only if it is not used for input
RC_INPUT_ROLL = 1
RC_INPUT_PITCH = 2
EXT_FC_INPUT_ROLL = 3
EXT_FC_INPUT_PITCH = 4
RC_INPUT_YAW = 5 (BOARD_VER >= 30)
PIN_AUX1* = 16
PIN_AUX2* = 17
PIN_AUX3* = 18
PIN_BUZZER* = 32
PIN_SSAT_POWER** = 33
* On boards v1.x (based on Atmega328p) PIN_AUX1..3 are not
present as outputs, and should be soldered to pin2, pin11,
pin12 of MCU correspondingly. PIN_BUZZER is mapped to
pin32 of MCU.

STATE 1u LOW = 0
HIGH = 1
LOW - pin can sink up to 40mA
HIGH - pin can source up to 40mA