Here is the information extracted from the ClientInterfaces_Primary.pdf document formatted into Markdown for a technical document/tutorial:

Primary and Secondary Interfaces

Primary Client Interface (10 Hz)

This section applies to UR software versions shown below:

Primary client: port 30001 (Robot state and messages)
Secondary client: port 30002 (Only robot state and the Version messages)
Primary client read only: port 30011 (Robot state and messages)
Secondary client read only: port 30012 (Only robot state and the Version messages)

Messages not documented in this manual are used internally by UR software and are not backwards compatible.

Field	Description
`int messageSize`	Length of overall package: total length of package including this field
`unsigned char messageType`	`MESSAGE_TYPE_ROBOT_STATE = 16`
Sub packages	Each sub package contains size, type, and package specific data

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_ROBOT_MODE_DATA = 0`
`uint64_t timestamp`
`bool isRealRobotConnected`
`bool isRealRobotEnabled`
`bool isRobotPowerOn`
`bool isEmergencyStopped`
`bool isProtectiveStopped`
`bool isProgramRunning`
`bool isProgramPaused`
`unsigned char robotMode`	Robot Modes
`unsigned char controlMode`	Control Modes
`double targetSpeedFraction`
`double speedScaling`
`double targetSpeedFractionLimit`
`unsigned char reserved`

Field	Description
`int packageSize`
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_JOINT_DATA = 1`
`double q_actual`
`double q_target`
`double qd_actual`
`float I_actual`
`float V_actual`
`float T_motor`
`float T_micro`	Deprecated - ignore
`uint8_t jointMode`	Joint Modes

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_TOOL_DATA = 2`
`unsigned char analogInputRange0`
`unsigned char analogInputRange1`
`double analogInput0`
`double analogInput1`
`float toolVoltage48V`
`unsigned char toolOutputVoltage`
`float toolCurrent`
`float toolTemperature`
`uint8_t toolMode`	Tool Modes

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_MASTERBOARD_DATA = 3`
`int digitalInputBits`
`int digitalOutputBits`
`unsigned char analogInputRange0`
`unsigned char analogInputRange1`
`double analogInput0`
`double analogInput1`
`char analogOutputDomain0`
`char analogOutputDomain1`
`double analogOutput0`
`double analogOutput1`
`float masterBoardTemperature`
`float robotVoltage48V`
`float robotCurrent`
`float masterIOCurrent`
`unsigned char safetyMode`	Safety Modes
`uint8_t InReducedMode`
`char euromap67InterfaceInstalled`
`uint32_t euromapInputBits`	If Euromap67 interface is installed
`uint32_t euromapOutputBits`	If Euromap67 interface is installed
`float euromapVoltage24V`	If Euromap67 interface is installed
`float euromapCurrent`	If Euromap67 interface is installed
`uint32_t`	Used by Universal Robots software only
`uint8_t operationalModeSelectorInput`
`uint8_t threePositionEnablingDeviceInput`
`unsigned char`	Used by Universal Robots software only

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_CARTESIAN_INFO = 4`
`double X`
`double Y`
`double Z`
`double Rx`
`double Ry`
`double Rz`
`double TCPOffsetX`
`double TCPOffsetY`
`double TCPOffsetZ`
`double TCPOffsetRx`
`double TCPOffsetRy`
`double TCPOffsetRz`

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_KINEMATICS_INFO = 5`
`uint32_t checksum`	For each joint
`double DHtheta`	For each joint
`double DHa`	For each joint
`double Dhd`	For each joint
`double Dhalpha`	For each joint
`uint32_t calibration_status`

This information is sent when leaving initializing mode and/or if the kinematics configuration is changed.

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_CONFIGURATION_DATA = 6`
`double jointMinLimit`	For each joint
`double jointMaxLimit`	For each joint
`double jointMaxSpeed`	For each joint
`double jointMaxAcceleration`	For each joint
`double vJointDefault`
`double aJointDefault`
`double vToolDefault`
`double aToolDefault`
`double eqRadius`
`double DHa`	For each joint
`double Dhd`	For each joint
`double DHalpha`	For each joint
`double DHtheta`	For each joint
`int32_t masterboardVersion`
`int32_t controllerBoxType`
`int32_t robotType`
`int32_t robotSubType`

This information is sent when leaving initializing mode and/or if the kinematics configuration is changed.

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_FORCE_MODE_DATA = 7`
`double Fx`
`double Fy`
`double Fz`
`double Frx`
`double Fry`
`double Frz`
`double robotDexterity`

Field	Description
`int packageSize`
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_ADDITIONAL_INFO = 8`
`unsigned char tpButtonState`
`bool freedriveButtonEnabled`
`bool IOEnabledFreedrive`
`unsigned char reserved`

Field	Description
`int packageSize`	Length

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_SAFETY_DATA = 10`
`uint64_t timestamp`
`uint8_t robotMessageType`
`uint8_t source`
`uint8_t robotMessageCode`

Field	Description
`int packageSize`	Length of Sub Package: total length of subpackage including this field
`unsigned char packageType`	`ROBOT_STATE_PACKAGE_TYPE_TOOL_COMM_INFO = 11`
`uint64_t timestamp`
`uint8_t toolCommMessageType`
`uint8_t toolCommMessageCode`