Samsung S5PC100, Руководство пользователя

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JPEG S5PC100 USER’S MANUAL (REV1.0)
9.4-10
With interrupt case 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.
To clear the interrupt case 2 is also done by reading JPGINTST and JPGOPR. If there is no error during header
parsing, it will be read as 0x08. The interrupt case 2 indicates that the decompression process is paused. Process
restarts by getting restart signal from software.
If interrupt case 3 occurs, TIMER_INT_STAT is read as 1 and it is cleared by writing 1 in TIMER_INT_STAT
register. In this case, JPEG needs reset or S/W reset before next operation.
If interrupt case 4 occurs, 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.
5.7 INTERRUPT SETTING
JPGINTSE register specifies whether the interrupt is allowed or not after header parsing and for illegal input file
for decompression.
To allow interrupt request after header analysis during decompression, set HEAD_INT_EN to 1, before start the
decompression process. If this interrupt occurs, JPEG pauses the decompression process (During the pause,
JPGOPR has value “1” because the process is not complete).
To deal with an illegal input JPEG file for decompression, set ERR_INT_EN to 0x7, before start the
decompression process. If input file is illegal, JPGINTST register shows abnormal value at the end of operation
(Normal value is 0x8 after header parsing and 0x40 after the end of operation).
To enable timer interrupt, set TIMER_INT_EN to 1 before start or restart.
To enable compressed stream size interrupt, set ENC_STREAM_INT_EN to 1 before starting compression.
5.8 S/W RESET
JPEG IP has a register for S/W reset. S/W reset is executed by following 3 steps.
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 IP is terminated abnormally or holds operation, S/W reset is needed to start new operation.
5.9 MARKER PROCESS
The following markers are generated during compression.