stlc5412 STMicroelectronics, stlc5412 Datasheet - Page 37

• Manufacturer Part Number: stlc5412
• Description: 2b1q U Interface Device Enhanced With Dect Mode
• Manufacturer: STMicroelectronics

ways to enter quiet mode: QM bit in CR6 register
and QM primitive command to write in TXACT
register; in this last case, any further primitive will
clear quiet mode.
AUTOMODE
For all auto mode configurations, AIS pin allows a
choice of line interface: 27 or 15mH for the trans-
former and resistors line or device side.
In NT1, the activation/deactivation state machine
and the automatic power-up / power-down capa-
bilities of the UID provide for a direct connection
through GCI between UID and SID-GCI (ST
5421) without the need of an extra microcontroller
(see figure 13b). LSD- pin of SID-GCI must be con-
nected together to the Bx input pin of UID to ensure
autonomous power-up/down control. Activation/De-
activation commands and indications are trans-
ferred from one device to the other by means of the
C/I channel. Maintenance functions are automat-
ically processed in UID. Therefore, there is no
transfer of messages on the Monitor channel be-
tween UID and SID-GCI. Please note that the
2B+D loop-back request at the S interface is pro-
vided using the C/I channel code ARL and that
there is not automatic processing of S and Q mes-
sages in SID-GCI.
In Repetor, the same advantages are provided by
a direct connection through GCI between both
UID without the need of an extra microcontroller
(see figure 13c). As for NT1, C/I channel transfers
activation/deactivation commands and indica-
tions. Maintenance functions are automatically
processed in UIDs, needing the transfer of eoc
messages, overhead bits and CRC fault detec-
tions. This is performed autonomously on the
Monitor channel by sending when required mes-
sages in a regular format as already described.
eoc messages are transmitted according to Table
5; overhead bits in the M4 channel excluding act,
dea, uoa and sai, are transferred transparently;
spare overhead bits in M5 or M6 bit positions are
also transferred transparently; febe and nebe bits
are transmitted according to Figure10.
COMMAND INDICATION (C/I) CODES
Activation, deactivation and some special test
functions can be initiated by the system by writ-
ing in TXACT register. Any status change of the
on-chip state machine is indicated to the system
by the UID by setting a new code in the RXACT
register. When GCI is selected, TXACT and
RXACT registers are normally associated with the
C/I channel (it is possible to associate them with
the MONITOR channel thank to the CID bit in
CR2 register). All commands and indications are
coded on four bits: C1, C2, C3, C4. Codes are
listed in Table 7. For each mode, a list of recog-
nized commands and generated indications is
given. Hereafter, you have a detailed description
of the codes depending on mode selected.
NT mode: Command
0000 (PUP): Power Up
When in the power down state, PUP command
powers up the device ready for a cold or a warm
start. When GCI is selected with clocks as out-
puts, PUP command is replaced by pulling low Bx
input pin.
0001 (RES): Reset
RES command resets UID ready for a cold start.
Configuration registers are not changed. RES can
be operated when the device is either powered up
or down.
If RES command is applied when the line is not
fully deactivated, UID properly ends the activation
before to come back in H1 state; In this case DP
or EIU indication is returned (Auto mode configu-
ration or not respectively).
0010 (SP1): Send Single Pulse +1 and -1
SP1 test command forces UID to send +1, -1,
pulses to the line, one pulse per frame.
0011 (RDT): Random Data Transmitted
RDT test command forces UID to send data with
random equiprobable levels at 80 kbaud.
0100 (EIS): Error Indicate S Interface
EIS command reports on the U line, a default on
the S interface.
0101 (PDN): Power Down
PDN command forces UID to power down state. It
should normally be used after UID has been set
in a known deactivated state, e.g. in an NT after a
DI status indication has been reported. In GCI, C/I
indication (DI) is sent twice on Br output before
UID powers down.
0110 (UAI): U interface Activation Indicate
UAI command is significant only when RR bit is
set equal one in CR2 register or if NT-RR-AUTO
auto-mode is selected. After the receiver has
been super-frame synchronized, UAI command
allows UID to send SN3 signal to the line.
0111 (QM): Quiet Mode
In this mode, UID does not react to any line status
change. UID can be powered up or down and
ready for a cold start or a warm start. All configu-
ration registers and coefficients remain un-
changed. Quiet Mode is disabled by any other
command.
Note: Inside UID, an logical or is implemented
with this QM primitive and the QM bit in CR6 reg-
ister.
1000 (AR): Activation Request
Beeing in the Power Up and deactivated state
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