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DS3171/DS3172/DS3173/DS3174
40
shows the relationship between the DS3 transmit overhead port pins.
Figure 8-10. DS3 Framing Transmit Overhead Port Timing
TOH
TOHSOF
TOHCLK
F74
C73
F73
1
2
3
4
5
6
7
8
9
10 11 12 13 14
16 17 18 19 20 21 22 23 24
15
F11
X1
F13
C12
F12
C13
F14
F21
C21
X2
F23
C22
F22
C23
F24
F31
C31
P1
C32
F32
TOHEN
C11
shows the relationship between the E3 G.751 transmit overhead port pins.
Figure 8-11. E3 G.751 Framing Transmit Overhead Port Timing
TOH
TOHSOF
TOHCLK
N
A
FAS
10
1
2
3
4
5
6
7
8
9
10 11 12 13 14
16 17 18 19 20 21 22 23 24
15
FAS
2
FAS
3
FAS
1
FAS
6
FAS
5
FAS
4
FAS
7
FAS
8
FAS
10
A
FAS
9
FAS
2
FAS
1
N
FAS
3
FAS
4
FAS
6
FAS
8
FAS
5
FAS
9
FAS
9
TOHEN
shows the relationship between the E3 G.832 transmit overhead port pins.
Figure 8-12. E3 G.832 Framing Transmit Overhead Port Timing
TOH
TOHCLK
GC
8
GC
7
GC
6
1
2
3
4
5
6
7
8
9
10 11 12
13 14
16 17 18 19 20 21 22 23 24
15
FA1
2
FA1
3
FA1
1
FA1
6
FA1
5
FA1
4
FA1
7
FA1
8
FA2
2
FA2
3
FA2
1
FA2
6
FA2
5
FA2
4
FA2
7
FA2
8
E M
2
E M
3
E M
1
E M
5
E M
4
TOHSOF
TOHEN
8.3.3 DS3/E3 Serial Data Interface
8.3.3.1 DS3/E3 SCT Mode Transmit Serial Interface Pin Functional Timing
The TSERn pin is used to input DS3 or E3 payload data bits in all framing modes as well as the C-bits, which can
be treated as payload, in DS3 M23 and E3 G.751 framing modes. The TDENn signal is used to determine the DS3
or E3 payload bit positions on TSERn. The TDENn signal goes high three clocks before the first bit of a payload
sequence is clocked into the TSERn pin and it goes low three clocks before the payload sequence is stopped
being clocked in to the TSERn pin. The TSOFOn signal pulses high three clocks before the start of the DS3 or E3
overhead bit position on TSERn. The TSOFIn pin is used to set the DS3 or E3 frame position. When the TSOFIn
pin transitions low to high, the first DS3/E3 overhead bit position on TSERn will be forced to align to it
show the relationship between the SCT transmit port pins.