6.2.6.11 Interlaced Frame Content

The LCDC supports progressive and interlaced content. Interlaced video signals provide only half the lines in each frame. Two fields are used alternately, each containing half the lines of the original frame. The top field, with index 0, contains every other line, starting with the first line. The bottom field, with index 1, contains every other line, starting with the second line. This is illustrated in the figure below.

Figure 6-9. Progressive and Interlaced Content

When this mode is selected, the Unified Scaling Engine is used to resample the current frame and interpolate the missing lines. To select Interlaced Content mode, set LCDC_HEOCFG1.ILD to one.

To handle both fields, specific configuration registers are duplicated depending on the field index, as described in the table below.

Table 6-57. Interlaced Configuration Registers
FieldProgressiveInterlaced Field 0 (Top)Interlaced Field 1 (Bottom)
Frame buffer address

LCDC_HEOYFBA0

LCDC_HEOCBFBA0

LCDC_HEOCRFBA0

LCDC_HEOYFBA1

LCDC_HEOCBFBA1

LCDC_HEOCRFBA1

Scaling pixel alignment

LCDC_HEOCFG28.VXYOFF

LCDC_HEOCFG28.VXCOFF

LCDC_HEOCFG30.VXSYCFG

LCDC_HEOCFG30.VXSCCFG

LCDC_HEOCFG28.VXYOFF1

LCDC_HEOCFG28.VXCOFF1

LCDC_HEOCFG30.VXSYCFG1

LCDC_HEOCFG30.VXSCCFG1