634 Backlight question


New member
I am using SPI to interface a PIC microcontroller to the 634. I cannot seem to activate the backlight. I have the LCD and LED pins tied to +5. The datasheet says that to turn on the backlight, I should send "\014\100" to the LCD. This command seems to do nothing. Different values for the backlight do not affect the LCD either. How am I supposed to turn on the backlight?

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CF Tech

The "\014" is a notation used in the data sheet and WinTest for 14 decimal. So you need to send 14 decimal, followed by 100 decimal to change the backlight.

Please give that a try.

By default, the backlight should be on. We sell modules that have no backlight. Are you sure you have a backlit module?