27 GRAPHICS ENGINE (GE)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
27-23
4.5.1 List of Calculation Errors
Table 27.
CALC_ERR[3:0]
Error
0xf to 0x9
Reserved
–
0x8
Decompress
A Decompress flag (0x80) exists in the image data specified by a decom-
pression command.
*
3
0x7
Picture header
The header of the image data specified by a decompression command is
invalid.
0x6
Font size
The character width or height specified by a character command is 0.
0x5
Radius
The radius specified by a circle/solid filled circle command is invalid (or
less than 1).
0x4
Circle location
No arc/circular section to be drawn is specified in a circle/solid filled circle
command.
0x3
Concave
An illegal quadrilateral (concave) is specified in a solid filled quadrilateral
command.
*
1
*
2
0x2
Coordinates
The area specified as the copy source in a copy command or clipping area
in a register configuration command is beyond the work area.
0x1
Trace width
An illegal line width (less than 1 or a value that exceeds the object size) is
specified in a object (line) drawing command.
0x0
No error
No error has occurred.
*
1 A calculation error and a drawing error (No VRAM write error) have occurred at the same time under the con-
ditions shown below.
a. When a Concave error (CALC_ERR[3:0] = 0x3) has occurred while calculation error interrupts are en-
abled (GE_ERR_IE1/GE_IE register = 1)
b. When a Decompress error (CALC_ERR[3:0] = 0x8) has occurred and the data placed at the front of the
invalid decompress flag (0x80) has not been written to the VRAM (drawing on outside the work area/clip
area or drawing with the transparent color)
No drawing error will occur when another calculation error has occurred.
*
2 Concave errors can be detected only when calculation error interrupts are enabled (GE_ERR_IE1 = 1). Other
calculation errors can always be detected regardless of the GE_ERR_IE1 setting.
*
3 The image data in which an error occurs will be drawn with the last valid color.
Note: Occurrence of a calculation error does not terminate command execution if calculation error inter-
rupts are disabled (GE_ERR_IE1 = 0). Although the command in which an error has occurred is
not executed, the subsequent commands are executed normally. In this case, CALC_ERR[3:0] is
not cleared. Be sure to clear CALC_ERR[3:0] before executing the subsequent command list.
When calculation error interrupts are enabled (GE_ERR_IE1 = 1), occurrence of an error termi-
nates command execution. In this case, no end-of-execution interrupt will occur.
Drawing errors
If an error is detected while the GE is writing data to the VRAM, the GE sets the corresponding error bit in
DRAW_ERR[3:0]/GE_IF2 register. A drawing error interrupt can be generated at this point. Read DRAW_
ERR[3:0] in the interrupt handler routine to identify the error that occur. The DRAW_ERR[3:0] bits that have
been set are cleared by writing 1.
4.5.2 List of Drawing Errors
Table 27.
DRAW_ERR[3:0]
Error
0b1000
No VRAM write
Data has not been written to the VRAM. The following shows leading
causes:
1. All the lines of the specified object are located out of the drawing area
(except when a block transfer command or a drawing command with re-
write effect is out of the range).
2. The object/image has only the transparent color (except when a copy
command or a block transfer command is executed, or the writing effect
of rewrite or mesh specifies the transparent color).
3. A Concave error (CALC_ERR[3:0] = 0x3)
*
has occurred when calcula-
tion error interrupts are enabled (GE_ERR_IE1 = 1).
0b0100
Color depth over The specified drawing color or a pixel color in the image data is out of the
effective range for the bpp mode set in the GE.