Nortel Circuit Card Installation Manual page 684

Page 684 of 906
Figure 162
NT8D41BA QSDI paddle board block diagram
decode logic
Processor
bus
System considerations
553-3001-211 Standard 3.00
NT8D41BA Quad Serial Data Interface Paddle Board
Other logic on the card includes baud rate generators, RS-232-C driver/
receiver pairs, and the switches and logic needed to configure each UART.
UARTs
UART
no. 1
UART
no. 2
UART
no. 3
UART
no. 4
Address
In dual-processor systems, the QSDI paddle board will behave differently
depending on which backplane socket it is installed. Installing the paddle
board into a socket in the network area of the backplane allows it to work
when either of the system processors is active. Installing the paddle board into
a socket in the CPU area of the backplane allows it to work only when that
CPU is active.
August 2005
RS-232-C
drivers and receivers
Clock and bit
rate select logic
TD
Port 1 J1
RD
TD
Port 2
RD
TD
J2
Port 3
RD
TD
Port 4
RD
553-5986