38.6.9.2 Horizontal Scaler

The XMEMSIZE field of the LCDC_HEOCFG4 register indicates the horizontal size minus one of the image in the system memory. The XSIZE field of the LCDC_HEOCFG3 register contains the horizontal size minus one of the window. The SCALEN bit of the LCDC_HEOCFG13 register is set to ‘1’. The scaling factor is programmed in the XFACTOR field of the LCDC_HEOCFG13 register. Use the following algorithm to find the XFACTOR value:

XFACTO R_{1 st} = floor (\frac{8 \times 256 \times XMEMSIZE - 256 \times XPHIDEF}{XSIZE})

XFACTO R_{1 st} = XFACTO R_{1 st} + 1

XME {MSIZE}_{\max} = floor (\frac{XFACTO R_{1 st} \times XSIZE + 256 \times XPHIDEF}{2048})

\{\begin{matrix} XFACTOR = XFACTO R_{1 st} - 1 when (XME {MSIZE}_{\max} > XMEMSIZE) \\ XFACTOR = XFACTO R_{1 st} otherwise \end{matrix}