MT9074_05 Datasheet, PDF (67/151 Pages) Zarlink Semiconductor Inc – T1/E1/J1 Single Chip Transceiver

MT9074
Data Sheet
Bit
Name
Functional Description
2
PERR
Payload Error Insertion. A zero - to - one transition of this bit inserts a
single bit error in the transmit payload. A one, zero or one-to-zero transition
has no function.
1
---
Unused.
0
LOS/LOF
Loss of Signal or Loss of Frame Selection. If one, pin LOS will go high
when a loss of signal state exists (criteria as per LLOS status bit). If low, pin
LOS will go high when either a loss of signal or a loss of frame alignment
state exits.
Table 30 - Error Insertion Word (T1)
(Page 1, Address 19H)
Bit
Name
Functional Description
7
RST
Software reset. Setting this bit is equivalent to performing a hardware
reset. All counters are cleared and the control registers are set to their
default values. This control bit is internally cleared after the reset operation
is complete.
6
SPND
Suspend Interrupts. If one, the IRQ output will be in a high-impedance
state and all interrupts will be ignored. If zero, the IRQ output will function
normally.
5
INTA
Interrupt Acknowledge. Setting this bit clears all the interrupt status bits
and forces the IRQ pin into high impedance. The control bit itself is then
internally cleared.
4
CNTCLR
Counter Clear. If one, all status error counters are cleared and held low.
3
SAMPLE
One Second Sample. Setting this bit causes the error counters (change of
frame alignment, loss of frame alignment, bpv errors, crc errors, severely
errored frame events and multiframes out of sync) to be updated on one
second intervals coincident with the one second timer (status page 3
address 12H bit 7).
2
EXTOSC
External Oscillator Select. Setting this bit connects the pin OSC1 to a TTL
compatible input. This allows for a system design employing a TTL output
oscillator as a 20.000 Mhz reference clock.
1
RSV
Reserved. Set to zero for normal operation.
0
RSV
Reserved. Set to zero for normal operation.
Table 31 - Reset Control Word (T1)
(Page 1, Address 1AH)
67
Zarlink Semiconductor Inc.