PXD20RM Datasheet, PDF (1572/1628 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

47.4.2 Application Information
Normally, the user shall not change the register values of the function enable bits, input/output video size,
color conversion coefficients, DMA_INC, MODE32BIT, scaling factors and B/C adjust loop-up-table
contents after VIU2 is started up. When video input source is changed, user should reset VIU2 and
re-configure related registers.
47.4.2.1 Register Configuration Timing Window
As mentioned above, dynamic configuration on registers is not recommended because it may cause error
if it’s not configured in a certain timing window, especially for INVSZ and DMA_INC.
Register configuration timing window is shown in below diagram. All registers, except SOFT_RESET bit,
are recommended to be configured during vertical blanking, after DMA transfer is done and field
identification bit is changed (field interrupt is asserted).
F
V
H
DMA_DONE
Configuration Timing Window
Figure 47-22. Register Configuration Timing Window
47-24
PXD20 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor