Specifications
Appendix C Operating Environment Installation and Operation Manual
C-2 E1 Environment FCD-E1LC Ver. 1.0
Time Slot 0 Time Slot 16 Time Slots 1-15, 17-31
FAS MAS
a. Even Frames (0,2,4-14)
b. Odd Frames (1,3,5-15)
a. Frame 0
b. Frames 1-15
Channel Data
10011011
I 1ANNNNN
0000XYXX
ABCDABCD 12345678
32 Time Slots/Frame
8 Bits per
Time Slot
16 Frames/Multiframe
TS
0
TS
1
TS
2
TS
3
TS
4
TS
5
TS
6
TS
7
TS
8
TS
9
TS
10
TS
11
TS
12
TS
13
TS
14
TS
15
TS
16
TS
17
TS
18
TS
19
TS
20
TS
21
TS
22
TS
23
TS
24
TS
25
TS
26
TS
27
TS
28
TS
29
TS
30
TS
31
FR
0
FR
1
FR
2
FR
3
FR
4
FR
5
FR
6
FR
7
FR
8
FR
9
FR
10
FR
11
FR
12
FR
13
FR
14
FR
15
Notes
ABCD
X
Y
MAS
I
N
A
FAS
International Bit
National Bits (S
a4
through S
a8
)
Alarm Indication Signal (Loss of Frame Alignment - Red Alarm)
Frame Alignment Signal, occupies alternate
(but not necessarily even) frames
ABCD Signaling Bits
Extra Bit
Loss of Multiframe Alignment
Multiframe Alignment Signal
Figure C-1. E1 Frame Format
G732N Multiframe
The G732N multiframe structure consists of two frames, which are identified by
means of the information included in timeslot 0:
• The even frame of the pair includes the frame alignment signal (FAS).
• The odd frame includes a “1” in bit position 2, and housekeeping information
in the other bits.
The number of timeslots available for user’s data is 31, and therefore the
maximum payload rate is 1984 kbps.
G732S Multiframe
The G732S multiframe includes 16 frames, which are identified by means of a
separate multiframe alignment signal (MAS) contained in timeslot 16 of frame
number 0 of each multiframe.
Since timeslot 16 must be reserved for the transmission of the MAS and system
signaling, only 30 timeslots are available for the user’s payload, and the maximum
payload rate is 1920 kbps.
When using the G732S multiframe format, timeslots 16 in the 16 frames of each
multiframe carry the following information:
• The first four bits of timeslot 16 of frame number 0 in multiframe 16 always
carry the multiframe alignment sequence, 0000.
• Bit 6 in timeslot 16 of frame number 0 in multiframe 16 is used to notify the
equipment at the other end of the link that the local equipment lost multiframe
alignment.
• The other bits of this timeslot are not assigned mandatory functions.