PXD10RM Datasheet, PDF (432/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

12.5.3 Error detection
The DCU asserts error flags when errors are detected in its configuration or when the user attempts to
modify the configuration at an invalid point in the panel refresh period or when it is unable to access the
required source data. The error flags may raise an interrupt if enabled to do so by the related mask bit in
the corresponding mask register.
Error flags are stored in the PARR_ERR_STATUS and INT_STATUS registers.
Errors in the DCU configuration are collected in the PARR_ERR_STATUS register. The flags
Ln_PARR_ERR (where n is the layer number) indicate an error in the configuration of the layer which can
be either an invalid tile mode size or a layer with a horizontal dimension that is smaller than the minimum
size defined by the layer encoding (see Section 12.4.5.3, Layer size and positioning”). The DISP_ERR flag
indicates that the VSYNC and HSYNC pulse widths are configured to the invalid value of 0. The
HWC_ERR flag indicates that the hardware cursor is either larger than the available memory or is placed
in an off-panel position. The SIG_ERR indicates that the signature calculation specifies an area that
extends beyond the panel size.
Reads of CLUT/Tile RAM during the period when the TFT LCD panel is being updated do not return the
CLUT/Tile RAM content.
Errors caused when the DCU is unable to access its required source data are collected in the INT_STATUS
register. These errors are indicated by the UNDRUN flag and the Pm_FIFO_LO_FLAG flags (where m is
the postion in the blend stack)
12.5.4 Interrupt generation
The DCU generates interrupt through four lines that are controlled by the contents of six registers:
• INT_STATUS
• INT_MASK
• PDI_STATUS
• MASK_PDI_STATUS
• PARR_ERR STATUS
• MASK_PARR_ERR STATUS
There are four interrupt status lines defined.These lines are grouped as follows
• Timing based interrupts:
— VSYNC
— LS_BF_VS
— VS_BLANK
— PROG_END
— DMA_TRANS_FINISH
• Functional interrupts:
— UNDRUN
— CRC_READY
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PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor