DLPU081B January 2019 – January 2024 DLPC3479
Table 3-2 describes the write parameters.
MSB | Byte 1 | LSB | |||||
---|---|---|---|---|---|---|---|
b7 | b6 | b5 | b4 | b3 | b2 | b1 | b0 |
Byte 1 | Operating Mode |
---|---|
00h | Display - External Video Mode |
01h | Display - Test Pattern Generator Mode |
02h | Display - Splash Screen Mode |
03h | Light Control – External Pattern Streaming Mode |
04h | Light Control – Internal Pattern Streaming Mode |
05h | Light Control – Splash Pattern Mode |
06h - FEh | Reserved |
FFh | Standby Mode |
The Standby mode disables illumination power and sets the DMD in a 50-50 refresh duty cycle, where the mirrors are on 50% of the time and off during the remaining time. This 50-50 refresh state helps in prolonging the life of the DMD.
The other operating modes have associated commands which are only applicable to that mode and must be run to properly configure the selected mode. The associated commands are listed below:
The table below show the source specific associated commands, where ‘Y’ represents a valid source selection and ‘N’ implies that the command is not supported by the selected source.
Source Specific Associated Commands | Display Modes | Light Control Modes | ||||
---|---|---|---|---|---|---|
External Video Port | Test Pattern Generator | Splash Screen | External Pattern Streaming | Internal Pattern Streaming | Splash | |
Write External Video Source Format Select | Y | N | N | Y | N | N |
Write External Input Image Size | Y | N | N | Y | N | N |
Write Test Pattern Select | N | Y | N | N | N | N |
Write Splash Screen Select | N | N | Y | N | N | Y |
Write Splash Screen Execute | N | N | Y(1) | N | N | Y(1) |
Write Pattern Configuration | N | N | N | Y | Y | Y |
Write Trigger Out Configuration | N | N | N | Y | Y | Y |
Write Trigger In Configuration | N | N | N | N | Y | N |
Write Pattern Ready Configuration | N | N | N | N | Y | N |
It is recommended that the source associated commands be sent prior to sending the Write Operating Mode Select command. These commands (except for Write Splash Screen Execute) describe the unique characteristics of their associated source, and once these settings have been defined, they are stored in a volatile manner. When source associated commands are sent when that source is not active, the controller software saves the new settings, but does not execute these commands. When that source becomes active (via the Write Operating Mode Select command), the controller applies these settings. Each time an operating mode selection is made , the system retrieves the settings defined previously and automatically applies them. As such, the user only needs to send these associated commands when the source first needs to be defined, or when the source characteristics for that port need to be changed. It is important to note that the appropriate associated commands must be updated when source characteristics change. See below for examples to configure different operating modes.
The rest of the commands that apply to image setup are those commands whose settings are applicable across all source selections, and indeed, these command settings would typically remain the same across the different Operating Mode selections. Sometimes the values for these commands are the same across the different input source types, but this does not indicate that hardware settings have not changed. For example, if the display image size is set to 720p and the external port input source size is set to VGA, the input scales up to the display size of 720p. The controller displays these settings at the resolution specified by Write Display Size (12h). Therefore, the scale settings must be changed. The controller software manages the underlying hardware settings. An example is shown below:
If source associated commands are sent for a source that is already active, the controller software will execute these commands when received. An example is shown below:
Refer to Write Image Freeze (1Ah) for information on hiding on-screen artifacts when selecting an input source.