Samsung S5PC110, Manual

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S5PC110_UM 12 11BJPEG
12-9
12.6.6 INTERRUPT SIGNAL
Interrupt signal is generated under the following conditions, and the JPGINTST register identifies causes:
1. Compression or decompression process for one picture is complete,
2. Internal timer counting ends before completion of compression or decompression.
3. During compression, the byte size of output stream is larger than the predefined bound size in
ENC_STREAM_BOUND.
In condition 1, the normal process is finished. To clear the interrupt request, read the JPGINTST register and
JPGOPR register. If there is no encoding or decoding error, JPGINTST must be read as 0x40. If another value is
read, the operation result may not be correct.
In condition 2, TIMER_INT_STAT is read as 1 and it is cleared by writing 1 in TIMER_INT_STAT register. In this
case, JPEG requires reset or S/W reset before next operation.
In condition 3, ENC_STREAM_INT_STAT is read as 1, JPEG operation is stopped and there is no further memory
access by JPEG. This interrupt is cleared by writing 1 in ENC_STREAM_INT_STAT register. In this case, JPEG
needs reset or S/W reset before next operation.
12.6.7 INTERRUPT SETTING
If this JPGINTSE register is set, it invokes the interrupt when the input file for decompression is illegal.
To enable timer interrupt, set TIMER_INT_EN to 1 before start or restart.
To deal with an illegal input jpeg file for decompression, set RSTm_INT_EN , DATA_NUM_INT_EN or FINAL
MCU_NUM_INT_EN.
To enable compressed stream size interrupt, set ENC_STREAM_INT_EN to 1 before starting compression.
12.6.8 S/W RESET
JPEG IP has a register for S/W reset. Steps to perform S/W reset:
1. Set 1 in the SW_RESET register.
2. Wait until SW_RESET register value changes to 0.
3. After the value changes to 0, set the proper register for next operation and start the operation.
If JPEG core is terminated abnormally or holds operation, S/W reset is needed to start new operation.