Documentation ¶
Overview ¶
Measures UV-A, UV-B and UV index.
See also the documentation here: https://www.tinkerforge.com/en/doc/Software/Bricklets/UVLightV2_Bricklet_Go.html.
Index ¶
- Constants
- type BootloaderMode
- type BootloaderStatus
- type Function
- type IntegrationTime
- type StatusLEDConfig
- type ThresholdOption
- type UVLightV2Bricklet
- func (device *UVLightV2Bricklet) DeregisterUVACallback(registrationId uint64)
- func (device *UVLightV2Bricklet) DeregisterUVBCallback(registrationId uint64)
- func (device *UVLightV2Bricklet) DeregisterUVICallback(registrationId uint64)
- func (device *UVLightV2Bricklet) GetAPIVersion() [3]uint8
- func (device *UVLightV2Bricklet) GetBootloaderMode() (mode BootloaderMode, err error)
- func (device *UVLightV2Bricklet) GetChipTemperature() (temperature int16, err error)
- func (device *UVLightV2Bricklet) GetConfiguration() (integrationTime IntegrationTime, err error)
- func (device *UVLightV2Bricklet) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, ...)
- func (device *UVLightV2Bricklet) GetResponseExpected(functionID Function) (bool, error)
- func (device *UVLightV2Bricklet) GetSPITFPErrorCount() (errorCountAckChecksum uint32, errorCountMessageChecksum uint32, ...)
- func (device *UVLightV2Bricklet) GetStatusLEDConfig() (config StatusLEDConfig, err error)
- func (device *UVLightV2Bricklet) GetUVA() (uva int32, err error)
- func (device *UVLightV2Bricklet) GetUVACallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...)
- func (device *UVLightV2Bricklet) GetUVB() (uvb int32, err error)
- func (device *UVLightV2Bricklet) GetUVBCallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...)
- func (device *UVLightV2Bricklet) GetUVI() (uvi int32, err error)
- func (device *UVLightV2Bricklet) GetUVICallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...)
- func (device *UVLightV2Bricklet) ReadUID() (uid uint32, err error)
- func (device *UVLightV2Bricklet) RegisterUVACallback(fn func(int32)) uint64
- func (device *UVLightV2Bricklet) RegisterUVBCallback(fn func(int32)) uint64
- func (device *UVLightV2Bricklet) RegisterUVICallback(fn func(int32)) uint64
- func (device *UVLightV2Bricklet) Reset() (err error)
- func (device *UVLightV2Bricklet) SetBootloaderMode(mode BootloaderMode) (status BootloaderStatus, err error)
- func (device *UVLightV2Bricklet) SetConfiguration(integrationTime IntegrationTime) (err error)
- func (device *UVLightV2Bricklet) SetResponseExpected(functionID Function, responseExpected bool) error
- func (device *UVLightV2Bricklet) SetResponseExpectedAll(responseExpected bool)
- func (device *UVLightV2Bricklet) SetStatusLEDConfig(config StatusLEDConfig) (err error)
- func (device *UVLightV2Bricklet) SetUVACallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...) (err error)
- func (device *UVLightV2Bricklet) SetUVBCallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...) (err error)
- func (device *UVLightV2Bricklet) SetUVICallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, ...) (err error)
- func (device *UVLightV2Bricklet) SetWriteFirmwarePointer(pointer uint32) (err error)
- func (device *UVLightV2Bricklet) WriteFirmware(data [64]uint8) (status uint8, err error)
- func (device *UVLightV2Bricklet) WriteUID(uid uint32) (err error)
Constants ¶
const DeviceDisplayName = "UV Light Bricklet 2.0"
const DeviceIdentifier = 2118
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type BootloaderMode ¶
type BootloaderMode = uint8
const ( BootloaderModeBootloader BootloaderMode = 0 BootloaderModeFirmware BootloaderMode = 1 BootloaderModeBootloaderWaitForReboot BootloaderMode = 2 BootloaderModeFirmwareWaitForReboot BootloaderMode = 3 BootloaderModeFirmwareWaitForEraseAndReboot BootloaderMode = 4 )
type BootloaderStatus ¶
type BootloaderStatus = uint8
const ( BootloaderStatusOK BootloaderStatus = 0 BootloaderStatusInvalidMode BootloaderStatus = 1 BootloaderStatusNoChange BootloaderStatus = 2 BootloaderStatusEntryFunctionNotPresent BootloaderStatus = 3 BootloaderStatusDeviceIdentifierIncorrect BootloaderStatus = 4 BootloaderStatusCRCMismatch BootloaderStatus = 5 )
type Function ¶
type Function = uint8
const ( FunctionGetUVA Function = 1 FunctionSetUVACallbackConfiguration Function = 2 FunctionGetUVACallbackConfiguration Function = 3 FunctionGetUVB Function = 5 FunctionSetUVBCallbackConfiguration Function = 6 FunctionGetUVBCallbackConfiguration Function = 7 FunctionGetUVI Function = 9 FunctionSetUVICallbackConfiguration Function = 10 FunctionGetUVICallbackConfiguration Function = 11 FunctionSetConfiguration Function = 13 FunctionGetConfiguration Function = 14 FunctionGetSPITFPErrorCount Function = 234 FunctionSetBootloaderMode Function = 235 FunctionGetBootloaderMode Function = 236 FunctionSetWriteFirmwarePointer Function = 237 FunctionWriteFirmware Function = 238 FunctionSetStatusLEDConfig Function = 239 FunctionGetStatusLEDConfig Function = 240 FunctionGetChipTemperature Function = 242 FunctionReset Function = 243 FunctionWriteUID Function = 248 FunctionReadUID Function = 249 FunctionGetIdentity Function = 255 FunctionCallbackUVA Function = 4 FunctionCallbackUVB Function = 8 FunctionCallbackUVI Function = 12 )
type IntegrationTime ¶
type IntegrationTime = uint8
const ( IntegrationTime50ms IntegrationTime = 0 IntegrationTime100ms IntegrationTime = 1 IntegrationTime200ms IntegrationTime = 2 IntegrationTime400ms IntegrationTime = 3 IntegrationTime800ms IntegrationTime = 4 )
type StatusLEDConfig ¶
type StatusLEDConfig = uint8
const ( StatusLEDConfigOff StatusLEDConfig = 0 StatusLEDConfigOn StatusLEDConfig = 1 StatusLEDConfigShowHeartbeat StatusLEDConfig = 2 StatusLEDConfigShowStatus StatusLEDConfig = 3 )
type ThresholdOption ¶
type ThresholdOption = rune
const ( ThresholdOptionOff ThresholdOption = 'x' ThresholdOptionOutside ThresholdOption = 'o' ThresholdOptionInside ThresholdOption = 'i' ThresholdOptionSmaller ThresholdOption = '<' ThresholdOptionGreater ThresholdOption = '>' )
type UVLightV2Bricklet ¶
type UVLightV2Bricklet struct {
// contains filtered or unexported fields
}
func New ¶
func New(uid string, ipcon *ipconnection.IPConnection) (UVLightV2Bricklet, error)
Creates an object with the unique device ID `uid`. This object can then be used after the IP Connection `ipcon` is connected.
func (*UVLightV2Bricklet) DeregisterUVACallback ¶
func (device *UVLightV2Bricklet) DeregisterUVACallback(registrationId uint64)
Remove a registered UVA callback.
func (*UVLightV2Bricklet) DeregisterUVBCallback ¶
func (device *UVLightV2Bricklet) DeregisterUVBCallback(registrationId uint64)
Remove a registered UVB callback.
func (*UVLightV2Bricklet) DeregisterUVICallback ¶
func (device *UVLightV2Bricklet) DeregisterUVICallback(registrationId uint64)
Remove a registered UVI callback.
func (*UVLightV2Bricklet) GetAPIVersion ¶
func (device *UVLightV2Bricklet) GetAPIVersion() [3]uint8
Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
func (*UVLightV2Bricklet) GetBootloaderMode ¶
func (device *UVLightV2Bricklet) GetBootloaderMode() (mode BootloaderMode, err error)
Returns the current bootloader mode, see SetBootloaderMode.
Associated constants:
- BootloaderModeBootloader
- BootloaderModeFirmware
- BootloaderModeBootloaderWaitForReboot
- BootloaderModeFirmwareWaitForReboot
- BootloaderModeFirmwareWaitForEraseAndReboot
func (*UVLightV2Bricklet) GetChipTemperature ¶
func (device *UVLightV2Bricklet) GetChipTemperature() (temperature int16, err error)
Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
func (*UVLightV2Bricklet) GetConfiguration ¶
func (device *UVLightV2Bricklet) GetConfiguration() (integrationTime IntegrationTime, err error)
Returns the configuration as set by SetConfiguration.
Associated constants:
- IntegrationTime50ms
- IntegrationTime100ms
- IntegrationTime200ms
- IntegrationTime400ms
- IntegrationTime800ms
func (*UVLightV2Bricklet) GetIdentity ¶
func (device *UVLightV2Bricklet) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an `Isolator Bricklet <isolator_bricklet>` is always at position 'z'.
The device identifier numbers can be found `here <device_identifier>`. |device_identifier_constant|
func (*UVLightV2Bricklet) GetResponseExpected ¶
func (device *UVLightV2Bricklet) GetResponseExpected(functionID Function) (bool, error)
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected. For setter functions it is disabled by default and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
See SetResponseExpected for the list of function ID constants available for this function.
func (*UVLightV2Bricklet) GetSPITFPErrorCount ¶
func (device *UVLightV2Bricklet) GetSPITFPErrorCount() (errorCountAckChecksum uint32, errorCountMessageChecksum uint32, errorCountFrame uint32, errorCountOverflow uint32, err error)
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into ¶
* ACK checksum errors, * message checksum errors, * framing errors and * overflow errors.
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
func (*UVLightV2Bricklet) GetStatusLEDConfig ¶
func (device *UVLightV2Bricklet) GetStatusLEDConfig() (config StatusLEDConfig, err error)
Returns the configuration as set by SetStatusLEDConfig
Associated constants:
- StatusLEDConfigOff
- StatusLEDConfigOn
- StatusLEDConfigShowHeartbeat
- StatusLEDConfigShowStatus
func (*UVLightV2Bricklet) GetUVA ¶
func (device *UVLightV2Bricklet) GetUVA() (uva int32, err error)
Returns the UVA intensity of the sensor. The sensor has not weighted the intensity with the erythemal action spectrum to get the skin-affecting irradiation. Therefore, you cannot just divide the value by 250 to get the UVA index. To get the UV index use GetUVI.
If the sensor is saturated, then -1 is returned, see SetConfiguration.
If you want to get the intensity periodically, it is recommended to use the RegisterUVACallback callback and set the period with SetUVACallbackConfiguration.
If you want to get the value periodically, it is recommended to use the RegisterUVACallback callback. You can set the callback configuration with SetUVACallbackConfiguration.
func (*UVLightV2Bricklet) GetUVACallbackConfiguration ¶
func (device *UVLightV2Bricklet) GetUVACallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32, err error)
Returns the callback configuration as set by SetUVACallbackConfiguration.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) GetUVB ¶
func (device *UVLightV2Bricklet) GetUVB() (uvb int32, err error)
Returns the UVB intensity of the sensor. The sensor has not weighted the intensity with the erythemal action spectrum to get the skin-affecting irradiation. Therefore, you cannot just divide the value by 250 to get the UVB index. To get the UV index use GetUVI.
If the sensor is saturated, then -1 is returned, see SetConfiguration.
If you want to get the intensity periodically, it is recommended to use the RegisterUVBCallback callback and set the period with SetUVBCallbackConfiguration.
If you want to get the value periodically, it is recommended to use the RegisterUVBCallback callback. You can set the callback configuration with SetUVBCallbackConfiguration.
func (*UVLightV2Bricklet) GetUVBCallbackConfiguration ¶
func (device *UVLightV2Bricklet) GetUVBCallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32, err error)
Returns the callback configuration as set by SetUVBCallbackConfiguration.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) GetUVI ¶
func (device *UVLightV2Bricklet) GetUVI() (uvi int32, err error)
Returns the UV index of the sensor, the index is given in 1/10.
If the sensor is saturated, then -1 is returned, see SetConfiguration.
If you want to get the intensity periodically, it is recommended to use the RegisterUVICallback callback and set the period with SetUVICallbackConfiguration.
If you want to get the value periodically, it is recommended to use the RegisterUVICallback callback. You can set the callback configuration with SetUVICallbackConfiguration.
func (*UVLightV2Bricklet) GetUVICallbackConfiguration ¶
func (device *UVLightV2Bricklet) GetUVICallbackConfiguration() (period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32, err error)
Returns the callback configuration as set by SetUVICallbackConfiguration.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) ReadUID ¶
func (device *UVLightV2Bricklet) ReadUID() (uid uint32, err error)
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
func (*UVLightV2Bricklet) RegisterUVACallback ¶
func (device *UVLightV2Bricklet) RegisterUVACallback(fn func(int32)) uint64
This callback is triggered periodically according to the configuration set by SetUVACallbackConfiguration.
The parameter is the same as GetUVA.
func (*UVLightV2Bricklet) RegisterUVBCallback ¶
func (device *UVLightV2Bricklet) RegisterUVBCallback(fn func(int32)) uint64
This callback is triggered periodically according to the configuration set by SetUVBCallbackConfiguration.
The parameter is the same as GetUVB.
func (*UVLightV2Bricklet) RegisterUVICallback ¶
func (device *UVLightV2Bricklet) RegisterUVICallback(fn func(int32)) uint64
This callback is triggered periodically according to the configuration set by SetUVICallbackConfiguration.
The parameter is the same as GetUVI.
func (*UVLightV2Bricklet) Reset ¶
func (device *UVLightV2Bricklet) Reset() (err error)
Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
func (*UVLightV2Bricklet) SetBootloaderMode ¶
func (device *UVLightV2Bricklet) SetBootloaderMode(mode BootloaderMode) (status BootloaderStatus, err error)
Sets the bootloader mode and returns the status after the requested mode change was instigated.
You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
Associated constants:
- BootloaderModeBootloader
- BootloaderModeFirmware
- BootloaderModeBootloaderWaitForReboot
- BootloaderModeFirmwareWaitForReboot
- BootloaderModeFirmwareWaitForEraseAndReboot
- BootloaderStatusOK
- BootloaderStatusInvalidMode
- BootloaderStatusNoChange
- BootloaderStatusEntryFunctionNotPresent
- BootloaderStatusDeviceIdentifierIncorrect
- BootloaderStatusCRCMismatch
func (*UVLightV2Bricklet) SetConfiguration ¶
func (device *UVLightV2Bricklet) SetConfiguration(integrationTime IntegrationTime) (err error)
Sets the configuration of the sensor. The integration time can be configured between 50 and 800 ms. With a shorter integration time the sensor reading updates more often but contains more noise. With a longer integration the sensor reading contains less noise but updates less often.
With a longer integration time (especially 800 ms) and a higher UV intensity the sensor can be saturated. If this happens the UVA/UVB/UVI readings are all -1. In this case you need to choose a shorter integration time.
Associated constants:
- IntegrationTime50ms
- IntegrationTime100ms
- IntegrationTime200ms
- IntegrationTime400ms
- IntegrationTime800ms
func (*UVLightV2Bricklet) SetResponseExpected ¶
func (device *UVLightV2Bricklet) SetResponseExpected(functionID Function, responseExpected bool) error
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
func (*UVLightV2Bricklet) SetResponseExpectedAll ¶
func (device *UVLightV2Bricklet) SetResponseExpectedAll(responseExpected bool)
Changes the response expected flag for all setter and callback configuration functions of this device at once.
func (*UVLightV2Bricklet) SetStatusLEDConfig ¶
func (device *UVLightV2Bricklet) SetStatusLEDConfig(config StatusLEDConfig) (err error)
Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.
Associated constants:
- StatusLEDConfigOff
- StatusLEDConfigOn
- StatusLEDConfigShowHeartbeat
- StatusLEDConfigShowStatus
func (*UVLightV2Bricklet) SetUVACallbackConfiguration ¶
func (device *UVLightV2Bricklet) SetUVACallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32) (err error)
The period is the period with which the RegisterUVACallback callback is triggered periodically. A value of 0 turns the callback off.
If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
It is furthermore possible to constrain the callback with thresholds.
The `option`-parameter together with min/max sets a threshold for the RegisterUVACallback callback.
The following options are possible:
Option| Description --- | --- 'x'| Threshold is turned off 'o'| Threshold is triggered when the value is *outside* the min and max values 'i'| Threshold is triggered when the value is *inside* or equal to the min and max values '<'| Threshold is triggered when the value is smaller than the min value (max is ignored) '>'| Threshold is triggered when the value is greater than the min value (max is ignored)
If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) SetUVBCallbackConfiguration ¶
func (device *UVLightV2Bricklet) SetUVBCallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32) (err error)
The period is the period with which the RegisterUVBCallback callback is triggered periodically. A value of 0 turns the callback off.
If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
It is furthermore possible to constrain the callback with thresholds.
The `option`-parameter together with min/max sets a threshold for the RegisterUVBCallback callback.
The following options are possible:
Option| Description --- | --- 'x'| Threshold is turned off 'o'| Threshold is triggered when the value is *outside* the min and max values 'i'| Threshold is triggered when the value is *inside* or equal to the min and max values '<'| Threshold is triggered when the value is smaller than the min value (max is ignored) '>'| Threshold is triggered when the value is greater than the min value (max is ignored)
If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) SetUVICallbackConfiguration ¶
func (device *UVLightV2Bricklet) SetUVICallbackConfiguration(period uint32, valueHasToChange bool, option ThresholdOption, min int32, max int32) (err error)
The period is the period with which the RegisterUVICallback callback is triggered periodically. A value of 0 turns the callback off.
If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
It is furthermore possible to constrain the callback with thresholds.
The `option`-parameter together with min/max sets a threshold for the RegisterUVICallback callback.
The following options are possible:
Option| Description --- | --- 'x'| Threshold is turned off 'o'| Threshold is triggered when the value is *outside* the min and max values 'i'| Threshold is triggered when the value is *inside* or equal to the min and max values '<'| Threshold is triggered when the value is smaller than the min value (max is ignored) '>'| Threshold is triggered when the value is greater than the min value (max is ignored)
If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.
Associated constants:
- ThresholdOptionOff
- ThresholdOptionOutside
- ThresholdOptionInside
- ThresholdOptionSmaller
- ThresholdOptionGreater
func (*UVLightV2Bricklet) SetWriteFirmwarePointer ¶
func (device *UVLightV2Bricklet) SetWriteFirmwarePointer(pointer uint32) (err error)
Sets the firmware pointer for WriteFirmware. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
func (*UVLightV2Bricklet) WriteFirmware ¶
func (device *UVLightV2Bricklet) WriteFirmware(data [64]uint8) (status uint8, err error)
Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer before. The firmware is written to flash every 4 chunks.
You can only write firmware in bootloader mode.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
func (*UVLightV2Bricklet) WriteUID ¶
func (device *UVLightV2Bricklet) WriteUID(uid uint32) (err error)
Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.
We recommend that you use Brick Viewer to change the UID.