Nortel DCT1900 Technical Product Manual page 176

Technical Product Manual - DCT1900
Installation Instructions, Central Processing Unit (CPU) – REX-BRD0004 or 2/ROFNB 157 19/2
Connectors
The CPU has the following front connectors (see Figure 5–4):
Sync in
Sync out (3x)
Printer port
PC port
GA port
The Sync In and Sync Out ports on the CPU are connected via two methods.
Method 1: Refer to Chapter 18, Synchronization Distribution Board and Chapter 20, Modular
Cabinet CPU Cabling. This method is the older method which incorporates an internally mounted,
inside the modular cabinet, Synch Distribution board and cables.
Method 2: Refer to Chapter 20, Modular Cabinet CPU Cabling, a newer method of connecting
sync cables directly between master and slave CPUs without using internally mounted sync board
and cables.
Note: The Sync Distribution Boad (SDB) and cables mentioned in method 1 are no longer
availabe or included in new systems. Method 2 must be used for any new installations or if the
SDB and cables must be replaced on an existing installation.
The SMS/printer, PC and general alarm ports are connected to the MCCB via factory installed
cables.
Interface characteristics of the printer and PC ports are:
asynchronous, 2400-115200 bit/s
8 data bits, 1 stop bit, no parity
X–on/X–off
LEDs
The following LEDs are located on the front of the CPU board:
LED1 Green
LED2 Red
LED3 Red
LED4 Red
LED5 Red
LED6 Green
Reset Button
The CPU is provided with a reset button. If this button is pressed, the CPU and the rest of the RE
are reset and perform a cold start as if the RE was switched off and on again.
Note:
Resetting the CPU may cause the synchronization slave CPUs, connected to this CPU, to lose
their synchronization. Immediate synchronization can be enforced by resetting the slave CPUs
after the synchronization master CPU has been reset. Bear in mind that a synchronization slave
CPU can be a clock provider to other slave CPUs.
5-4
: Normally on. Power On LED
: Normally off. Watch–dog LED
: Normally lit very weak. Communication with backplane LED
(not significant)
: Normally off. Board Error LED
: Normally off. Info, error or service message received, but not
read yet
: Test and Maintenance active. On during actual testing, or
during RS232 activity on the PC port.
Install-DCT1900/R8/mw
© 2000-2005