Use this function to use the underline mode of a lcd. All data will appear underlined when using this function call. The function demands the data to be underlined as first parameter.

Some LCDs have a controller onboard providing a underline mode. With this property the lcd can underline data displayed by the lcd. But in the most cases the underline mode is slow and take negative impact on cpu usage. For example LCDs having M50530 Chip onboard can underline data.