pef20320 Infineon Technologies Corporation, pef20320 Datasheet - Page 100

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

User’s Manual
TMR
Receive Direction
General Features
1. The starting and the ending flag (00 00
2. The number of bits within a frame is checked to be divisible by 8.
3. The number of bytes within a frame is checked to be smaller than MFL.
More detailed description of the individual features
1. a. A frame is supposed to have started after a sequence of 16 zeros a ‘1’-bit is
2. The check is reported in the NOB bit in the last receive descriptor of the frame.
3. The check is reported in the LFD bit in the last receive descriptor of the frame.
characters of the starting flag and the last character of the ending flag is extracted.
b. A frame is supposed to have stopped if
NOB = 1
NOB = 0
If NOB = 1 the last byte of the last access to a receive data section of the frame may
contain erroneous bits and shouldn’t be evaluated. This does not affect the reception
of frames with n +
LFD = 1
LFD = 0
MFL + 1
the receive data section of the frame may contain erroneous bits and shouldn’t be
evaluated.
LFD is always accompanied by NOB.
recognized. The frame is supposed to have this ‘1’-bit as first bit.
– either a sequence of 16 ‘zeros’ and a ‘one’ is found in the data stream after the
– or a sequence of 16 zeros is found octet synchronous (i.e. the first bit of the
In both cases the eighth bit of the sequence 00 00
the frame.
frame has started
sequence 00 00
integer m).
st
the number of bytes was greater than MFL.
the number of bytes was smaller or equal to MFL.
one are transferred to the shared memory. The bytes of the last access to
the bit length of the frame was not divisible by 8.
the bit length of the frame was divisible by 8.
1
/
2
octets
H
is the 8m + 1
st
100
bit since the starting ‘1’-bit of 1.a. for an
H
) is recognized. Interframe time-fill, both
H
is supposed to be the last bit of
Functional Description
PEB 20320
01.2000