User manual

Functional description VL6180X
20/79 DocID026171 Rev 6
2.6 Interrupt modes
The VL6180X can be configured to generate an ALS or range interrupt flag under any of the
following conditions:
• New sample ready
• Level low (RESULT__RANGE_VAL < SYSRANGE__THRESH_LOW)
• Level high (RESULT__RANGE_VAL > SYSRANGE__THRESH_HIGH)
• Out of window (RESULT__RANGE_VAL < SYSRANGE__THRESH_LOW) OR
(RESULT__RANGE_VAL > SYSRANGE__THRESH_HIGH)
In new sample ready mode, an interrupt flag will be raised at the end of every measurement
irrespective of whether the measurement is valid or if an error has occurred. This mode is
particularly useful during development and debug. In level interrupt mode the system will
raise an interrupt flag if either a low or high programmable threshold has been crossed. Out
of window interrupt mode activates both high and low level thresholds allowing a window of
operation to be specified. Interrupt modes for Range and ALS are configured via register
SYSTEM__INTERRUPT_CONFIG_GPIO{0x14}.
Note: In level or window interrupt modes range errors will only trigger an interrupt if the logical
conditions described above are met.
2.7 Range error codes
The system carries out a number of range checks during every range measurement to
ensure the validity of each range result. Register RESULT__RANGE_STATUS{0x4D}
returns an error code if one of the checks fails. Table 8 gives a summary of the possible
error codes.
Table 7. Typical range convergence time (ms)
Range (mm)
Target reflectance
3% 5% 17% 88%
10 0.43 0.33 0.18 0.18
20 0.94 0.73 0.28 0.18
30 1.89 1.40 0.51 0.18
40 3.07 2.25 0.81 0.18
50 4.35 3.24 1.18 0.24
60 5.70 4.22 1.60 0.32
70 7.07 5.35 2.07 0.49
80 8.41 6.45 2.58 0.50
90 9.58 7.56 3.14 0.61
100 10.73 8.65 3.69 0.73