FT800 Series Programmer Guide
Version 2.1
Document Reference No.: BRT_000030 Clearance No.: BRT#037
149
Copyright © Bridgetek Limited
Only signed and unsigned integers are supported in CMD_NUMBER (fractional part is not
supported).
The behavior of widgets is not defined if the input parameters values are outside the
valid range.
5.5
Fault Scenarios
Some commands can cause co-processor engine faults. These faults arise because the
co-processor engine cannot continue. For example:
An invalid JPEG is supplied to CMD_LOADIMAGE
An invalid data stream is supplied to CMD_INFLATE
An attempt is made to write more than 2048 instructions into a display list
In the fault condition, the co-processor engine sets REG_CMD_READ to 0xfff (an illegal
value because all command buffer data shall be 32-bit aligned), raises the
INT_CMDEMPTY interrupt, and stops accepting new commands. When the host MCU
recognizes the fault condition, it should recover as follows:
Set REG_CPURESET to 1, to hold the co-processor engine in the reset
condition
Set REG_CMD_READ and REG_CMD_WRITE to zero
Set REG_CPURESET to 0, to restart the co-processor engine
5.6
widgets physical dimension
This section contains the common physical dimensions of the widgets.
All rounded corners have a radius that is computed from the font used for the
widget (curvature of lowercase 'o' character). The radius is computed as Font
height*3/16
All 3D shadows are drawn with: (1) highlight offset 0.5 pixels above and left
of the object (2) shadow offset 1.0 pixel below and right of the object.
For widgets such as progress bar, scrollbar and slider, the output widget will
be a vertical widget in case width and height are of same value.
5.7
widgets color settings
Co-processor engine widgets are drawn with the color designated by the precedent
commands: CMD_FGCOLOR, CMD_BGCOLOR and COLOR_RGB. According to these
commands, the co-processor engine will determine to render the different area of co-
processor engine widgets in different color.
Usually, CMD_FGCOLOR affects the interaction area of co-processor engine widgets if
they are designed for interactive UI element, for example, CMD_BUTTON, CMD_DIAL.
CMD_BGCOLOR applies to the co-processor engine widgets with background. Please see
the table below for more details.
