Iot.Device.SenseHat.LedMatrixExt 1.0.2

Iot.Device.SenseHat.LedMatrixExt

Extension methods of SenseHatLedMatrix to show unicode letter, message, or series values on Raspberry Pi Sense HAT running on Linux.

Getting started

• Create a new console app (e.g. dotnet new console -o SenseHat.Sample).

• Install Iot.Device.SenseHat.LedMatrixExt from NuGet (e.g. navigate inside the project directory and run dotnet add package Iot.Device.SenseHat.LedMatrixExt).

• Explore the sample app SenseHat.QuickStart on how to build and run the app.

Extension methods of SenseHatLedMatrix

• Clear LED Matrix

ledMatrix.Clear(Color? backColor = null)

• Show a single letter (Unicode supported)

ledMatrix.ShowLetter(char letter, Color? foreColor = null, Color? backColor = null, Rotation rotation = Rotation.Rotate0)

• Show a message (Unicode supported)

ledMatrix.ShowMessage(string message, Color? foreColor = null, Color? backColor = null, Rotation textRotation = Rotation.Rotate0, Direction scrollDirection = Direction.Left, int speedInMs = 90)

• Show a series of values

ledMatrix.ShowSeriesValues(float[] values, Color? foreColor = null, Color? backColor = null, bool fill = false, Rotation rotation = Rotation.Rotate0, bool forward = true, int speedInMs = 90)

Unicode 8 x 8 Font

Built-in unicode characters

• U+0000 - U+007F (basic latin)
• U+00A0 - U+00FF (extended latin)
• U+0390 - U+03C9 (greek characters)
• U+3040 - U+309F (Hiragana)
• U+2500 - U+257F (box drawing)
• U+2580 - U+259F (block elements)
• U+E541 - U+E55A (standard galactic alphabet)

Add custom characters

See section Encoding for glyph.

Font8x8.AddGlyph(char letter, byte[] glyph)

Encoding

Every character in the font is encoded row-wise in 8 bytes.

The most significant bit of each byte corresponds to the first pixel in a row.

The character 'A' (0x41 / 65) is encoded as { 0x30, 0x78, 0xCC, 0xCC, 0xFC, 0xCC, 0xCC, 0x00 }

0x30 => 0011 0000 => ..XX....
0x78 => 0111 1000 => .XXXX...
0xCC => 1100 1100 => XX..XX..
0xCC => 1100 1100 => XX..XX..
0xFC => 1111 1100 => XXXXXX..
0xCC => 1100 1100 => XX..XX..
0xCC => 1100 1100 => XX..XX..
0x00 => 0000 0000 => ........

To access the nth pixel in a row, right-shift by 7-n.

                     . . X X . . . .
                     | | | | | | | |
(0x30 >> 7) & 1 == 0-+ | | | | | | |
(0x30 >> 6) & 1 == 0---+ | | | | | |
(0x30 >> 5) & 1 == 1-----+ | | | | |
(0x30 >> 4) & 1 == 1-------+ | | | |
(0x30 >> 3) & 1 == 0---------+ | | |
(0x30 >> 2) & 1 == 0-----------+ | |
(0x30 >> 1) & 1 == 0-------------+ |
(0x30 >> 0) & 1 == 0---------------+

Acknowledgements

Font8x8: https://github.com/dhepper/font8x8