Scrolls a message across one or more LEDs.
Project Designer allows you to create a list of segmented LEDs (1 or more) and the marquee allows you to scroll a longer message across this line of LEDs. The AxonII has a single LED built in.
The library allows you to control the scroll speed as well as the 'pause' before repeating the message again.
When the message is scrolling across the marquee then there will be a brief flash if, and only if, the displayed characters for frame N are the same as for frame N-1. So if the message 'Webbot' is being scrolled across a single LED then there will be a brief flash to separate the two 'b' characters. However: there would be not flash if there are two leds as the sequence 'We', 'eb', 'bb', 'bo' and 'ot' are all unique.
The message will not appear until an end of line character '\n' has been received.
The marquee is set up as an output stream so you can use all of the 'print' and '<<' commands to send data to it.
- isActive - Does the marquee have an active scrolling message?
- print - Prints the value of a number, or a string, to the stream.
- print_P - Prints a string from program memory to the stream.
- println - Sends a carriage return line feed sequence to the stream to indicate the end of a line of text.
- read - Reads the next byte from the device. This will return EOF, the end of file marker, if there are no characters available - otherwise it will return the next byte.
- setCharDelay - Change the duration (in microseconds) for scrolling characters in the marquee.
- setEndDelay - Change the delay for an auto-repeating message or make it non-repeating by specifying a delay of 0.
- write - Writes a single byte to the output stream. The returned value is normally the same value as the byte just written but on some devices it can return EOF to indicate a write error. For eaxmple: writing a byte out to a file stored on a µSD card may return EOF if there is no available space.
- write - Writes out a sequence of bytes from a given position in RAM. The returned value is the number of bytes actually written. This would only be less than the reqested number of bytes if there is an error writing to the stream.
- write_P - Writes out a sequence of bytes from a given position in program memory. The returned value is the number of bytes actually written. This would only be less than the reqested number of bytes if there is an error writing to the stream.