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Preliminary Information
MT9075A
4-165
Bit
Name
Functional Description
7
MFSYI
Multiframe
Interrupt.
(MFSYI = 1), an interrupt is initiated
when multiframe synchronization is
lost. Interrupt vector = 10000000.
Synchronization
When
unmasked
6
CSYNI
CRC-4
Synchronization Interrupt.
When
unmasked (CSYNI = 1), an interrupt
is initiated when CRC-4 multiframe
synchronization is lost. Interrupt
vector = 10000000.
Multiframe
5
- - -
Unused.
4
YI
Remote
Alarm Interrupt.
When unmasked
(YI = 1), an interrupt is initiated
when a remote signalling multiframe
alarm signal is received. Interrupt
vector = 10000000.
Signalling
Multiframe
Table 25: Interrupt Mask Word Three
(Page 01H, Address 1EH)
3
1SECI
One Second Status Interrupt.
When unmasked (1SECI = 1), an
interrupt is initiated when the 1SEC
status bit (page 03H, address 12H,
bit 7) changes from zero to one.
Interrupt vector = 00001000.
2
T1I
T1
unmasked (T1I = 1), an interrupt is
initiated when the T1 timer bit (page
03H, address 12H, bit 5) changes
from zero to one. Interrupt vector =
00001000.
Timer
Interrupt.
When
1
T2I
T2
unmasked (T2I = 1), an interrupt is
initiated when the T2 timer bit (page
03H, address 12H, bit 4) changes
from zero to one. Interrupt vector =
00001000.
Timer
Interrupt.
When
0
- - -
Unused
Bit
Name
Functional Description
Table 25: Interrupt Mask Word Three
(Page 01H, Address 1EH)
Bit
Name
Functional Description
7-3
---
Unused.
Set low for normal operation.
2-0
TX2-0
Transmit pulse amplitude.
Select the
TX2-TX0 bits according to the line type,
value of termination resistors (R
T
), and
transformer turns ratio used
TX2 TX1 TX0 Line(
) R
T
(
) Xfmr
0 0 0 120 0 1:2
0 0 1 120 0 1:1
0 1 0 120 15 1:2
0 1 1 120/75 12.1 1:2
1 0 0 75 0 1:2
1 0 1 75 0 1:1
1 1 1 75 9.1 1:2
1 1 1 75/120 12.1 1:2
Table 26: Transmit Pulse Control Word