pef20320 Infineon Technologies Corporation, pef20320 Datasheet - Page 119

• Manufacturer Part Number: pef20320
• Description: Multichannel Network Interface Controller For Hdlc With 32 Channels
• Manufacturer: Infineon Technologies Corporation

V.110/X.30
Receive Direction
General Features
In receive direction
– the starting sequence (00
– the synchronization pattern is monitored, after 3 consecutive
– a change of E-, S-, X-bits is monitored and reported by an interrupt.
– the data bits are extracted and written into the data section.
More detailed description of the individual features:
1. and 2. the receiver can be in one of 2 states:
Figure 69
Data extraction and monitoring of a change of E-, S-, X-bits and synchronization pattern
is only performed in synchronized state.
In the asynchronous state the receiver waits for the synchronization patter. The ‘1’-bit is
then interpreted as bit 1 of octet 2.
3. During the synchronized state a change of E, S, X-bits from one frame to the next and
4. The bits written into the data section are marked by
User’s Manual
loss of synchronism is detected.
erroneous frames a loss of synchronism is detected.
even within a frame (for SA, SB bits) is monitored. Only one interrupt per frame is
reported even if SA e.g. changes 3 times within the frame. The E-, S-, X-bits reported
in the interrupt are S9 for SB and S8 for SA and the second occurrence of X for X.
shown, bits repeated in the serial data are only strobed than at their last instance.
8 * "0" bit followed
by a "1" bit
H
followed by a ‘1’-bit) after initialization of
Unsynchronous State
Synchronous State
RESET
119
ITD05039
3 Consecutive Erroneous Frames
(with a Frame Error)
O
in Table 2 to Table 4. As
Functional Description
PEB 20320
01.2000