User Manual

About the TCP Protocol Version 1.2
This protocol defines the communication standard between third-party applications (“Client”)
and DaVinci Resolve (“Server”) using the TCP protocol.
Port number 9060 will be used by the server. SSL will not be used in this protocol.
Communication takes the form of request-response messages, where the Client initiates a
command, and the Server responds appropriately.
To use this protocol, you must first type the following string into the Advanced panel of the
DaVinci Resolve System Preferences:
System.Remote.Control = 1
Data Types
The following data types are used in this protocol:
 float (f): A 4-byte IEEE 754 single precision float
 int (i): A 4-bytes signed int
 unsigned char (uc): A 1-byte unsigned char (0–255)
 string (s): A UTF-8 encoded string. No terminator is specified. The string is a composite
type, transmitted as a single int (i) specifying the number of characters in the string (N),
followed by N unsigned chars (uc) containing the letters of the string.
NOTE: The bytes of the float and int types are transmitted in little endian order.
Command Format
Commands are transmitted as a single string (using characters a–z (0x61 – 0x7A) only), followed
by any additional payload required by the command in the definition.
Response Format
The response to any command is composed of a status byte (unsigned char), followed by any
additional payload required by the response.
Communication Delays
Once the first byte of the command string is sent, the rest of the command string and the
payload data must follow without delay. At the end of COMMAND, the server must respond
immediately. If there is a delay of more than 5 seconds during this process, the party waiting for
data may drop the connection assuming that the peer has become unresponsive.
There is currently no limit on the delay between two consecutive commands. (NOTE:
Alternatively, a maximum allowable delay may be defined, in which case, the client may issue
periodic ‘connect’ commands to keep the connection alive.)
Status Response Values
The meaning of the status values are as follows:
 0x00: Command was executed successfully. Any additional payload is
sentasexpected.
 0xFF: Command could not be executed successfully. No additional payload will follow.
Chapter – 175 TCP Protocol for DaVinci Resolve Transport Control 3541