Messages

All messages start with a uint8 indicating the message type, followed by zero or more fields specific to that message type.

Unless otherwise specified, all message fields are little-endian, and strings are null-terminated.

Message type quick reference

Type ID (base 10)	Type ID (base 16)	Message
0	0x00	InfoRequest
1	0x01	InfoResponse
10	0x0A	StartFirmwareUploadRequest
11	0x0B	StartFirmwareUploadResponse
12	0x0C	StartFileUploadRequest
13	0x0D	StartFileUploadResponse
16	0x10	TransferChunkRequest
17	0x11	TransferChunkResponse
20	0x14	BeginFirmwareUpdateRequest
21	0x15	BeginFirmwareUpdateResponse
22	0x16	SetHubNameRequest
23	0x17	SetHubNameResponse
24	0x18	GetHubNameRequest
25	0x19	GetHubNameResponse
26	0x1A	DeviceUuidRequest
27	0x1B	DeviceUuidResponse
30	0x1E	ProgramFlowRequest
31	0x1F	ProgramFlowResponse
32	0x20	ProgramFlowNotification
70	0x46	ClearSlotRequest
71	0x47	ClearSlotResponse
33	0x21	ConsoleNotification
50	0x32	TunnelMessage
40	0x28	DeviceNotificationRequest
41	0x29	DeviceNotificationResponse
0	0x00	DeviceBattery
1	0x01	DeviceImuValues
2	0x02	Device5x5MatrixDisplay
10	0x0A	DeviceMotor
11	0x0B	DeviceForceSensor
12	0x0C	DeviceColorSensor
13	0x0D	DeviceDistanceSensor
14	0x0E	Device3x3ColorMatrix
60	0x3C	DeviceNotification

---

0x00 InfoRequest

Format	Description
uint8	Message type (0x00)

0x01 InfoResponse

Format	Description
uint8	Message type (0x01)
uint8	RPC major version.
uint8	RPC minor version.
uint16	RPC build number.
uint8	Firmware major version.
uint8	Firmware minor version.
uint16	Firmware build number.
uint16	Maximum packet size in bytes.
uint16	Maximum message size in bytes.
uint16	Maximum chunk size in bytes.
uint16	Product Group Device type.

---

0x0A StartFirmwareUploadRequest

Format	Description
uint8	Message type (0x0A)
uint8[20]	File SHA.
uint32	CRC32 for the file.

0x0B StartFirmwareUploadResponse

Format	Description
uint8	Message type (0x0B)
uint8	Response Status.
uint32	Number of bytes already uploaded for this File SHA. Used to resume an interrupted upload.

---

0x0C StartFileUploadRequest

Format	Description
uint8	Message type (0x0C)
string[32]	Name of the file as it will be stored on the hub.
uint8	Program slot to store the file in.
uint32	CRC32 for the file.

0x0D StartFileUploadResponse

Format	Description
uint8	Message type (0x0D)
uint8	Response Status.

---

0x10 TransferChunkRequest

Format	Description
uint8	Message type (0x10)
uint32	Running CRC32 for the transfer.
uint16	Chunk payload size.
uint8[size]	Chunk payload.

0x11 TransferChunkResponse

Format	Description
uint8	Message type (0x11)
uint8	Response Status.

---

0x14 BeginFirmwareUpdateRequest

Format	Description
uint8	Message type (0x14)
uint8[20]	File SHA.
uint32	CRC32 for the file.

0x15 BeginFirmwareUpdateResponse

Format	Description
uint8	Message type (0x15)
uint8	Response Status.

---

0x16 SetHubNameRequest

Format	Description
uint8	Message type (0x16)
string[30]	New hub name.

0x17 SetHubNameResponse

Format	Description
uint8	Message type (0x17)
uint8	Response Status.

---

0x18 GetHubNameRequest

Format	Description
uint8	Message type (0x18)

0x19 GetHubNameResponse

Format	Description
uint8	Message type (0x19)
string[30]	Hub name.

---

0x1A DeviceUuidRequest

Format	Description
uint8	Message type (0x1A)

0x1B DeviceUuidResponse

Format	Description
uint8	Message type (0x1B)
uint8[16]	Device UUID.

---

0x1E ProgramFlowRequest

Format	Description
uint8	Message type (0x1E)
uint8	Program Action.
uint8	Program slot to use.

0x1F ProgramFlowResponse

Format	Description
uint8	Message type (0x1F)
uint8	Response Status.

0x20 ProgramFlowNotification

Format	Description
uint8	Message type (0x20)
uint8	Program Action.

---

0x46 ClearSlotRequest

Format	Description
uint8	Message type (0x46)
uint8	Program slot to clear.

0x47 ClearSlotResponse

Format	Description
uint8	Message type (0x47)
uint8	Response Status.

---

0x21 ConsoleNotification

Format	Description
uint8	Message type (0x21)
string[256]	Console message.

0x32 TunnelMessage

Format	Description
uint8	Message type (0x32)
uint16	Payload size in bytes.
uint8[size]	Payload data.

---

0x28 DeviceNotificationRequest

Format	Description
uint8	Message type (0x28)
uint16	Desired notification interval in milliseconds. (0 = disable)

0x29 DeviceNotificationResponse

Format	Description
uint8	Message type (0x29)
uint8	Response Status.

0x3C DeviceNotification

Format	Description
uint8	Message type (0x3C)
uint16	Payload size in bytes.
uint8[size]	Payload as an array of device messages (see below).

Device messages

The DeviceNotification payload is a sequence of device messages.

Like the standard messages, device messages start with a uint8 indicating how to interpret the rest of the message.

0x00 DeviceBattery

Format	Description
uint8	Message type (0x00)
uint8	Battery level in percent.

0x01 DeviceImuValues

Format	Description
uint8	Message type (0x01)
uint8	Hub Face pointing up.
uint8	Hub Face configured as yaw face.
int16	Yaw value in respect to the configured yaw face.
int16	Pitch value in respect to the configured yaw face.
int16	Roll value in respect to the configured yaw face.
int16	Accelerometer reading in X axis.
int16	Accelerometer reading in Y axis.
int16	Accelerometer reading in Z axis.
int16	Gyroscope reading in X axis.
int16	Gyroscope reading in Y axis.
int16	Gyroscope reading in Z axis.

0x02 Device5x5MatrixDisplay

Format	Description
uint8	Message type (0x02)
uint8[25]	Pixel value for display.

0x0A DeviceMotor

Format	Description
uint8	Message type (0x0A)
uint8	Hub Port the motor is connected to.
uint8	Motor Device Type.
int16	Absolute position in degrees, in the range -180 to 179.
int16	Power applied to the motor, in the range -10000 to 10000.
int8	Speed of the motor, in the range -100 to 100.
int32	Position of the motor, in the range -2147483648 to 2147483647.

0x0B DeviceForceSensor

Format	Description
uint8	Message type (0x0B)
uint8	Hub Port the force sensor is connected to.
uint8	Measured value, in the range 0 to 100.
uint8	0x01 if the sensor detects pressure, 0x00 otherwise.

0x0C DeviceColorSensor

Format	Description
uint8	Message type (0x0C)
uint8	Hub Port the color sensor is connected to.
int8	Color detected by the sensor.
uint16	Raw red value, in the range 0 to 1023.
uint16	Raw green value, in the range 0 to 1023.
uint16	Raw blue value, in the range 0 to 1023.

0x0D DeviceDistanceSensor

Format	Description
uint8	Message type (0x0D)
uint8	Hub Port the distance sensor is connected to.
int16	Measured distance in millimeters, in the range 40 to 2000. (-1 if no object is detected.)

0x0E Device3x3ColorMatrix

Format	Description
uint8	Message type (0x0E)
uint8	Hub Port the color matrix is connected to.
uint8[9]	Displayed pixel values. Each pixel is encoded with the brightness in the high nibble and the color in the low nibble.