zl50064 Zarlink Semiconductor, zl50064 Datasheet - Page 35

• Manufacturer Part Number: zl50064
• Description: 16 K Channel Digital Switch With High Jitter Tolerance, Single Rate 2, 4, 8 Or 16 Mbps And 64 Input And 64 Output Streams
• Manufacturer: Zarlink Semiconductor

11.4
The Backplane Connection Memory (BCM) has 8,192 addresses of 16-bit words. Each address, accessed through
bits A13-A0 of the microprocessor port, is allocated to an individual Backplane output stream and channel. The bit
definition for each 16-bit word is presented in Table 11 for Source-to-Backplane connections.
The most-significant bit in the memory location, BSRC, selects the switch configuration for Local-to-Backplane or
Backplane-to-Backplane. When the per-channel Message Mode is selected (BMM memory bit = HIGH), the lower
byte of the BCM word (BCAB[7:0]) will be transmitted as data on the output stream (BSTo0-31) in place of data
defined by the Source Control, Stream and Channel Address bits.
12:8
Bit
7:0
Bit
15
14
13
15
14
Backplane Connection Memory Bit Definition
LSAB[4:0]
LCAB[7:0]
Name
LSRC
Name
BSRC
LMM
BMM
LE
Local Source Control Bit
When LOW, the source is from the Backplane input port (Backplane Data Memory).
When HIGH, the source is from the Local input port (Local Data Memory).
Ignored when LMM is set HIGH.
Local Message Mode Bit
When LOW, the channel is in Connection Mode (data to be output on channel originated in
Local or Backplane Data Memory).
When HIGH, the channel is in Message Mode (data to be output on channel originated in
Local Connection Memory).
Local Output Enable Bit
When LOW, the channel may be high impedance, either at the device output, or set by an
external buffer dependent upon the LORS pin.
When HIGH, the channel is active.
Source Stream Address Bits
The binary value of these 5 bits represents the input stream number.
Ignored when LMM is set HIGH.
Source Channel Address Bits / Message Mode Data
The binary value of these 8 bits represents the input channel number when LMM is set
LOW.
Transmitted as data when LMM is set HIGH.
Note: When LMM is set HIGH, in both ST-BUS and GCI-Bus modes, the LCAB[7:0] bits are
output sequentially to the timeslot with LCAB[7] being output first.
Backplane Source Control Bit
When LOW, the source is from the Local input port (Local Data Memory).
When HIGH, the source is from the Backplane input port (Backplane Data Memory).
Ignored when BMM is set HIGH.
Backplane Message Mode Bit
When LOW, the channel is in Connection Mode (data to be output on channel originated in
Backplane or Local Data Memory).
When HIGH, the channel is in Message Mode (data to be output on channel originated in
Backplane Connection Memory).
Table 11 - BCM Bits for Source-to-Backplane Switching
Table 10 - LCM Bits for Source-to-Local Switching
Zarlink Semiconductor Inc.
ZL50062/4
35
Description
Description
Data Sheet