ST STM32L4+ Series Reference Manual page 896

LCD-TFT display controller (LTDC)
The dithering can be switched on and off on the fly through the LTDC_GCR register.
Reload shadow registers
Some configuration registers are shadowed. The shadow registers values can be reloaded
immediately to the active registers when writing to these registers or at the beginning of the
vertical blanking period following the configuration in the LTDC_SRCR register. If the
immediate reload configuration is selected, the reload must be activated only when all new
registers have been written.
The shadow registers must not be modified again before the reload is done. Reading from
the shadow registers returns the actual active value. The new written value can only be read
after the reload has taken place.
A register reload interrupt can be generated if enabled in the LTDC_IER register.
The shadowed registers are all layer1 and layer2 registers except LTDC_LxCLUTWR.
Interrupt generation event
Refer to
29.5.2 Layer programmable parameters
Up to two layers can be enabled, disabled and configured separately. The layer display
order is fixed and it is bottom up. If two layers are enabled, the layer2 is the top displayed
window.
Windowing
Every layer can be positioned and resized and it must be inside the active display area.
The window position and size are configured through the top-left and bottom-right X/Y
positions and the internal timing generator that includes the synchronous, back porch size
and the active data area. Refer to LTDC_LxWHPCR and LTDC_WVPCR registers.
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Section 29.6: LTDC interrupts for the interrupt configuration.
RM0432 Rev 6
RM0432