Freescale Semiconductor S08 manual User Interface Menu

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PC Control Mode

Figure 3-3. User Interface Menu

When the MCU receives a control command or PWM input data from the PC, the firmware interprets the information to take the corresponding actions. It may update the output PWM values in next PWM duty or delivery of the corresponding LED control parameter back to the PC. Three timer channels in the timer 1 module are configured to edge-aligned PWM operation mode. This generates the PWM signals for the RGB color channels.

By the proper control of the RGB channel PWM, the LED box can provide different lighting effects.

If you select the white balance mode to AUTO, the LED output gives a white color output. The firmware retains control of the RGB PWM ratio based on the preset white color. You can adjust the output brightness by pressing the + or − key in the host PC keyboard. Alternatively, you can input a green channel PWM value and the firmware calculates the blue and red PWM values to give the resultant intensity.

A demonstration display feature is available. After enabling this feature, the firmware adjusts RGB PWM so the light box switches among different preset colors, delivery fade in and fade out lighting effects, etc.

You can also set the PWM to different frequencies. At a lower PWM frequency, such as 30 Hz, the flicking phenomenon is more noticeable. This phenomenon can be minimized or removed by setting the PWM frequency to a higher value.

There are examples at the end of this section showing how to control the LED box through the host PC.

LED Lighting Control using the MC9S08AW60, Rev. 1

Freescale Semiconductor

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Contents LED Lighting Control Using the MC9S08AW60 Page Revision History LED Lighting Control using the MC9S08AW60Designer Reference Manual Freescale Semiconductor Table of Contents Appendix a Schematics Appendix B Bill of Materials Chapter Introduction FeaturesIntroduction MC9S08AW60 System OverviewDevices in the MC9S08AW60/48/32/16 Series Peripherals Available per Package Type Introduction LED Lighting Control using the MC9S08AW60, Rev AW60 Control Board Chapter Hardware DescriptionDEMO9S08AW60LED Layout DEMO9S08AW60LED FeaturesReset Switch PowerDevelopment Support Clock SourceLED Indicators Pushbutton SwitchesUser Options ADC InterfaceIIC Port Other I/O ConnectorsSCI Port SPI PortLED Light Box Interface PWM Port10. Sensor Interface Type a 11. Sensor Interface Type H 12. Temperature Sensor Input13. User Assignable Input LED Driving Board RGB LED Chip LED Driver Design ProceduresBoost Converter Current Sense ResistorEquations for Boost Converter Freescale Semiconductor Firmware Flow Main Program Chapter Firmware DescriptionFirmware Flow PWM Adjustment PC Control ModeUser Interface Menu Standalone Mode Firmware Files Freescale Semiconductor Hardware and Software Setup Chapter Demo SetupHardware Setup PC Software SetupEcho Typed Characters Setting Demo 1 Demonstration Display Demo ExamplesDemo 3 Auto White Balance Control Demo 2 Preset Colors DisplayDemo 4 PWM Output Frequency Control Demo 5 Full Manual ControlProgram the MCU Flash TroubleshootingDemo Setup Appendix a Schematics LED Lighting Control using the MC9S08AW60, Rev LED Lighting Control using the MC9S08AW60, Rev LED Lighting Control using the MC9S08AW60, Rev LED Lighting Control using the MC9S08AW60, Rev LED Lighting Control using the MC9S08AW60, Rev Appendix B Bill of Materials Part Description Quantity Value Designators BOM for AW60 Control BoardValue Designators BOM for LED Driving BoardLED Lighting Control using the MC9S08AW60, Rev Page How to Reach Us