This document describes the uplink and downlink message payloads used by the asset tracker. The payload sizes have been restricted to a maximum of 19 bytes which is the maximum payload size available for the CSS/LoRA PHY type on the Amazon Sidewalk network.
| TYPE Value | Name | Description |
|---|---|---|
| 0 | CONFIG | Describes the current configuration of the asset tracker |
| 1 | NOLOC | Current ambient data only. Sent if no location data is available. |
| 2 | WIFI | Current ambient and WiFi location data |
| 3 | GNSS | Current ambient and partial GNSS location data in a sequence of messages |
The devices can send two different types of uplink messages: CONFIG and data (NOLOC, WIFI, GNSS). The config message is sent at device start and on response to a config downlink. The data messags are sent at regular intervals determined by the configuration or are triggered by the USER button on the WioTracker 1110.
| Name | Type | Device Time | SW Version | Stored Rec Count | Link / Location Mode | Motion Period | Motion Sampling Freq | Motion Threshold | Static Sampling Freq |
| Position | 0x00 | Bytes 2 - 5 | Byte 6 | Bytes 7 - 8 | Byte 9 | Byte 10 | Byte 11 | Byte 12 | Byte 13 |
Description:
| Byte Offset | Name | Data Type | Description |
|---|---|---|---|
| 0 | Type | uint_8 | CONFIG message type (0) ex. 0x00 = CONFIG message |
| 1-4 | Device Time | uint_32 | Epoche time from device in seconds. ex. 0x65073638 = 1694971448 = Sun, 17 Sep 2023 17:24:08 GMT |
| 5 | SW Version | uint_8 | bit 7-4: Major SW Version bit 3-0: Minor SW Version ex. 0x11 = SW v1.1 |
| 6-7 | Stored Record Count(n) | uint_16 | Current location record count stored in onboard flash. ex. 0x1234 = 4660 location records stored |
| 8 | Sidewalk Link Type & Location Scanning Modes | uint_8 | bit 7-4: Sidewalk Link Type -->0b0000 = 0x0 = BLE -->0b0001 = 0x1 = FSK (not used/implemented) -->0b0010 = 0x2 = LoRa bit 3-0: Location Scanning Mode -->0b0000 = 0x0 = WiFi Only -->0b0001 = 0x1 = GNSS Only -->0b0010 = 0x2 = WiFi + GNSS ex 0x22 = LoRa Link and WiFi + GNSS scanning |
| 9 | Motion Period(min) | uint_8 | Period of time in minutes the device will stay in the motion state measured from when the motion threshold was last crossed. ex. 0x05 - 5min |
| 10 | Motion Sampling Frequency (s) | uint_8 | Frequency in seconds for sampling location data and attempting uplinks while device is in the motion state. (Minimum value = 30s) ex. 0x3C = 60s |
| 11 | Motion Threshold(g) | uint_8 | Acceleration(g) setting for determining whether the tracker is static or in motion. ex. TBD |
| 12 | Static Sampling Frequecy (min) | uint_8 | Frequency in hours for sampling location data and attempting uplinks while device is in the static state. (Minimum value = 15 - disabled/always in motion) ex. 0x3C = 60min sample and uplink frequecy |
| Name | Type | Reserved | Temp & Humidity | Motion State & Max Accel |
| Position | 0x10 | Byte 2 | Byte 3 | Byte 4 |
Description:
| Byte Offset | Name | Data Type | Description |
|---|---|---|---|
| 0 | Type | uint_8 | NOLOC message type bit 7-6: TYPE = 1 (NOLOC) bit 5-0: Unused ex. 0x40 = NOLOC type |
| 1 | Reserved | uint_8 | Reserved |
| 2 | Temp & Humidity | uint_8 | bit 7-4: Temperature (C) bit 3-0: Relative Humidity (%) ex. TBD |
| 3 | Motion State & Max Accel | uint_8 | bit 7: Motion state bit 6-0: Max accelleration since last record ex. TBD |
| Name | Type | Reserved | Temp & Humidity | Motion State & Max Accel | WiFi Location Data |
| Position | 0x20 | Byte 2 | Byte 3 | Byte 4 | Bytes 5 - 18 |
Description:
| Byte Offset | Name | Data Type | Description |
|---|---|---|---|
| 0 | Type | uint_8 | WIFI message type bit 7-6: TYPE = 2 (WIFI) bit 5-3: total fragments bit 2-0: current fragment *ex. 0x20 = WIFI type * |
| 1 | Reserved | uint_8 | Reserved |
| 2 | Temp & Humidity | uint_8 | bit 7-4: Temperature (C) bit 3-0: Relative Humidity (%) ex. TBD |
| 3 | Motion State & Max Accel | uint_8 | bit 7: Motion state bit 6-0: Max accelleration since last record ex. TBD |
| 5-19 | WiFi Location Data | byte 5: RSSI 1 byte 6-11: MAC 1 byte 12: RSSI 2 byte 13-18: MAC 2 |
| Name | Type / Seq>0 | GNSS Location Data |
| Position | 0x3X | Bytes 2 - 19 |
| Name | Type & Seq=0 | Battery | Temp & Humidity | Motion State & Max Accel | GNSS Data Size | Capture Time |
| Position | 0x30 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Bytes 5-8 |
Description:
| Byte Offset | Name | Data Type | Description |
|---|---|---|---|
| 0 | Type | uint_8 | GNSS message type bit 7-6: TYPE = 3 (GNSS) bit 5-0: Sequence number *ex. 0x30 = GNSS seq start * |
| 1 | Reserved | uint_8 | Reserved |
| 2 | Temp & Humidity | uint_8 | bit 7-4: Temperature (C) bit 3-0: Relative Humidity (%) ex. TBD |
| 3 | Motion State & Max Accel | uint_8 | bit 7: Motion state bit 6-0: Max accelleration since last record ex. TBD |
| 4 | GNSS Data Size | TBD | |
| 5-8 | Capture Time | TBD |
| Name | Type / Seq>0 | GNSS Location Data |
| Position | 0x3X | Bytes 2 - 19 |
Description:
| Byte Offset | Name | Data Type | Description |
|---|
The asset tracker supports a single downlink message type (Type=0 - CONFIG) that can be used to update the configuration on the device and send lifecycle commands.
| TYPE Value | Name | Description |
|---|---|---|
| 0 | CONFIG | Config and commands for the asset tracker |
| Name | Type & Command | Device Time | Max Records Stored | Link / Location Mode | Motion Period | Motion Sampling Freq | Motion Threshold | Static Sampling Freq | |
| Position | Byte 1 | Bytes 2 - 3 | Bytes 4 - 5 | Bytes 7 - 8 | Byte 9 | Byte 10 | Byte 11 | Byte 12 | Byte 13 |
TODO Description:
| Byte Offset | Name | Data Type | Description |
|---|---|---|---|
| 0 | Type | uint_8 | CONFIG message type (0) ex. 0x00 = CONFIG message |
| 1-4 | Device Time | uint_32 | Epoche time from device in seconds. ex. 0x65073638 = 1694971448 = Sun, 17 Sep 2023 17:24:08 GMT |
| 5 | SW Version | uint_8 | bit 7-4: Major SW Version bit 3-0: Minor SW Version ex. 0x11 = SW v1.1 |
| 6-7 | Stored Record Count(n) | uint_16 | Current location record count stored in onboard flash. ex. 0x1234 = 4660 location records stored |
| 8 | Sidewalk Link Type & Location Scanning Modes | uint_8 | bit 7-4: Sidewalk Link Type -->0b0000 = 0x0 = BLE -->0b0001 = 0x1 = FSK (not used/implemented) -->0b0010 = 0x2 = LoRa bit 3-0: Location Scanning Mode -->0b0000 = 0x0 = WiFi Only -->0b0001 = 0x1 = GNSS Only -->0b0010 = 0x2 = WiFi + GNSS ex 0x22 = LoRa Link and WiFi + GNSS scanning |
| 9 | Motion Period(min) | uint_8 | Period of time in minutes the device will stay in the motion state measured from when the motion threshold was last crossed. ex. 0x05 - 5min |
| 10 | Motion Sampling Frequency (s) | uint_8 | Frequency in seconds for sampling location data and attempting uplinks while device is in the motion state. (Minimum value = 30s) ex. 0x3C = 60s |
| 11 | Motion Threshold(g) | uint_8 | Acceleration(g) setting for determining whether the tracker is static or in motion. ex. TBD |
| 12 | Static Sampling Frequecy (hr) | uint_8 | Frequency in hours for sampling location data and attempting uplinks while device is in the static state. (Minimum value = 0 - disabled/always in motion) ex. 0x01 = 1hr sample and uplink frequecy |