MT9075A
Preliminary Information
Bit
Name
Functional Description
Bit
Name
Functional Description
CNTCLR
2
Counter Clear. If one, all status
counters are cleared and held low.
Zero for normal operation.
7
ODE
Output Data Enable. If one, the
DSTo and CSTo output drivers
function normally. When low, DSTo
and CSTo will be tristated.
1
MSN
Most
Nibble. If one, the CSTo and CSTi
channel associated signalling
Significant
Signalling
Note: When ODE =1, DSTo and
CSTo can be individually tristated
by DSToDE and CSToDE (page
01H, address 16H) respectively.
nibbles will be valid in the most
significant portion of each ST-BUS
time slot. If zero, the CSTo and
CSTi channel associated signalling
nibbles will be valid in the least
significant portion of each ST-BUS
time slot.
6
SPND Suspend Interrupts. If one, the
IRQ output (pin 12 in PLCC, 85 in
MQFP) will be in a high-impedance
state and all interrupts will be
ignored. If zero, the IRQ output will
function normally.
64KCCS
0
64 Kbits/s Common Channel
Signalling. If one, common channel
signalling information is sourced
from CSTi, and common channel
signalling information is clocked out
of CSTo. The transmit clock is an
internal clock. This 64 KHz clock is
divided down from C4b and is
synchronous with the STBUS
channel boundaries. The rising
edges of the clock occur between
channels 1 and 2; 5 and 6; 9 and
10; 13 and 14; 17 and 18; 21 and
22; 25 and 26; 29 and 30. The
receive clock is synchronous with
the same channel times, but derived
from the extracted clock timebase.
The CCS receive clock is driven out
on Rx64KCK (pin 47 in PLCC, 35 in
MQFP) when this bit is set.
5
4
INTA
Interrupt Acknowledge. A zero-to-
one or one-to-zero transition will
clear any pending interrupt and
make IRQ high.
TxCCS Transmit
Common
Channel
Signalling. If one, the transmit
section of the device is in common
channel signalling (CCS) mode. If
zero, it is in Channel Associated
Signalling (CAS) mode.
3
RPSIG Register
Programmed
Signalling. If one, the transmit CAS
signalling will be controlled by
programming page 05H. If zero, the
transmit CAS signalling will be
controlled through the CSTi stream.
Table 21 - Interrupt, Signalling and BERT
Control Word (Page 01H, Address 1AH)
(continued)
Table 21 - Interrupt, Signalling and BERT
Control Word (Page 01H, Address 1AH)
4-162
MITEL [ MITEL NETWORKS CORPORATION ]
