| ECC1C 145-944-00

Lens Compensations

Lens Compensations control system ID: 0xC8

- Current Mode - directly feeds through current
- Focal Power Mode - applies 1st and 2nd order Temperature compensation corrections, as well as “Membrane Creep” corrections

At startup, the 9 drift parameters are read from the device EEPROM.
At every time step when controlling the lens the following calculations have to be performed:

- get desired focal power (sfp[n]), measured Temperature (T[n])
- unit drift compensation, range: (0,1), captures dynamic behaviour described by T1up, T1down,T2,T3,T4
- gain temperature compensation: G1, G2 and G3 need to be corrected for T[n]
- scaled drift compensation: mapping of normalised dynamics to focal power (dpt) with G1’,G2’,G3’,G4, sfp[n]
- difference sfp[n] – z[n] gives a focal power that will be used for the usual focal power mode (temperature compensation lookup)
- from the lookup (5) we get a current value sc[n] that is set to the lens

### Register Map:

Address | Name | Default | Description | Type | Access
--- | --- | --- | --- | --- | ---
0xC800 | dpt | 0.0 | diopter | float | read only
0xC801 | current | 0.0 | output current | float | read only
0xC802 | filtercoefficent_a | 0.0 | filtercoefficent_a | float | read only
0xC803 | filtercoefficent_b | 0.0 | filtercoefficent_b | float | read only
0xC804 | filterF1 | 0.0 | filterF1 | float | read only
0xC805 | filterF2 | 0.0 | filterF2 | float | read only
0xC806 | filterF3 | 0.0 | filterF3 | float | read only
0xC807 | filterF4 | 0.0 | filterF4 | float | read only
0xC808 | Gain_Variable | 1 | Gain_Variable | float | read write
0xC809 | creepcompensation | 0.0 | creepcompensation | float | read only
0xC80A | part_config | 0 | part_config | float | read write
0xC80B | driftValue | 0.0 | driftValue | float | read only
0xC80C | minLimitForYellowFlag | 0.0 | min Limit For Yellow Flag | float | read only
0xC80D | maxLimitForYellowFlag | 0.0 | max Limit For Yellow Flag | float | read only
0xC80E | minLimitForRedFlag | 0.0 | min Limit For Red Flag | float | read only
0xC80F | maxLimitForRedFlag | 0.0 | max Limit For Red Flag | float | read only
0xC810 | minLimitForScrollFlag | 0.0 | min Limit For Scroll Flag | float | read only
0xC811 | maxLimitForScrollFlag | 0.0 | max Limit For Scroll Flag | float | read only
0xC812 | minGuaranteedTemperature | 0.0 | min guaranteed Temperature | float | read write
0xC813 | maxGuaranteedTemperature | 0.0 | max guaranteed Temperature | float | read write