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(a) Status transition
The receive pointer may be in one of three statuses, NORM, LOP, or AIS, as shown in Figure 3-10,
depending on the values of the extracted H1 and H2 bytes.
The overall status of the pointer changes depending on the status transition caused by the pointer
processing of H1#1 and H2#1 and on the status transition of each pointer caused by the concatenation
indication processing of H1#2 and H2#2 to H1#12 and H2#12.
The µ PD98413 has two mode of status transition, Bellcere mode and ITU-T mode. In the Bellcore mode,
H1#1 and H2#1, H1#2 and H2#2 to H1#12 and H2#12 is processed one sequencer and the overall status is
decided this one sequencer. In the ITU-T mode, H1#1 and H2#1, H1#2 and H2#2 to H1#12 and H2#12 is
processed each sequencer(total 12 sequencer) and the overall status is decided these sequencer.
However, by setting the ITUM bit of the MDPTRR register, the status transition mode is changed.
NORM status:
The receive pointer is normal and data can be received normally.
AIS status:
An abnormality occurs in an upstream device or transmission path. Data cannot be received
normally.
LOP status:
The receive pointer value is not normal. Data cannot be received normally.
CHAPTER 3 FUNCTIONAL OUTLINE
Figure 3-10. Pointer Status Transition
NORM
LOP
PRELIMINARY
AIS
NEC confidential and Proprietary
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