Yoctopuce Yocto-Display, User Manual

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Font bitmap example
The font file contains the following data:
Offset 0 1 2 3 4 5 6 7 8 9 A B C D E F
00000000 59 46 01 01 30 00 06 01 30 39 03 00 05 00 09 00
00000010 0D 00 11 00 15 00 19 00 1D 00 21 00 25 00 EB BA
00000020 3B BB B8 00 A8 8A 22 0A A8 00 AB BA BB 8B B8 00
00000030 AA 0B 8A 8A 88 00 EB B8 BB 8B B8 00 00 00 00 00
00000040 00 00
Note that the bitmap width must be a multiple of 16 pixels and that the height cannot be above 255
pixels. Moreover, blank spaces between two characters are encoded directly in the image. You do
not have to leave a blank space below the characters if you do not intend to use your font in console
mode.
You can find in the Delphi library a small Windows tool
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enabling you to generate font files from the
system fonts.
3.7. Sequences and animations
You can pre-program animations and play them as background tasks. To do so, you must call the
newSequence method of the Display object, then call the available graphical methods. You can
insert waiting times with pauseSequence . When you are done recording the sequence components,
call saveSequence . The sequence is then saved in the Yocto-Display file system. You can play it
back at will with playSequence . You can create loops by calling playSequence within a sequence.
You can find in the libraries a code sample
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illustrating how sequences work. As soon as this
example is run, the screen starts playing the sequence indefinitely.
Be aware that sequences change the values of the layer parameters (current point, current color,
etc.) with which they work. If you use a sequence as an animation in background task, make sure to
work with a different layer than the one used by your sequence.
Startup sequence
When your Yocto-Display is powered on, it runs the yocto.seq sequence which is hard-coded inside
the module. But you can configure your module so that it runs a sequence that you have chosen.
3.8. Optimizations
While the Yocto-Display has its own processor and offers numerous graphical routines, it stays a
relatively slow system compared to a classic display system. This slowness is the result of using the
HID protocol so that the Yocto-Display can be driven without drivers. The transfer rate between the
screen and the computer is limited to 64Ko per second. Each request takes up about 3ms. However,
there are techniques to optimize display.
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Examples\Display-font-generator
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Prog-Display-Sequences
3. Working principles
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