zl50052 Zarlink Semiconductor, zl50052 Datasheet - Page 25

• Manufacturer Part Number: zl50052
• Description: 8 K Channel Digital Switch With High Jitter Tolerance, Single Rate 32 Mbps , And 16 Inputs And 16 Outputs
• Manufacturer: Zarlink Semiconductor

8.0
The device includes two connection memories, the Local Connection Memory and the Backplane Connection
Memory.
8.1
The Local Connection Memory (LCM) is a 16-bit wide memory with 4,096 memory locations to support the Local
output port. The most significant bit of each word, bit[15], selects the source stream from either the Backplane
(LSRC = LOW) or the Local (LSRC = HIGH) port and determines the Backplane-to-Local or Local-to-Local data
routing. Bits[14:13] select the control modes of the Local output streams, the per-channel Message Mode and the
per-channel high impedance output control modes. In Connection Mode (bit[14] = LOW), bits[12:0] select the
source stream and channel number as detailed in Table 2. In Message Mode (bit[14] = HIGH), bits[12:8] are unused
and bits[7:0] contain the message byte to be transmitted. Bit[13] must be HIGH for Message Mode to ensure that
the output channel is not tri-stated.
8.2
The Backplane Connection Memory (BCM) is a 16-bit wide memory with 4,096 memory locations to support the
Backplane output port. The most significant bit of each word, bit[15], selects the source stream from either the
Backplane (BSRC = HIGH) or the Local (BSRC = LOW) port and determines the Local-to-Backplane or
Backplane-to-Backplane data routing. Bit[14:13] select the control modes of the Backplane output streams, namely
the per-channel Message Mode and the per-channel high impedance output control mode. In Connection Mode
(bit[14] = LOW), bits[12:0] select the source stream and channel number as detailed in Table 2. In Message Mode
(bit[14] = HIGH), bits[12:8] are unused and bits[7:0] contain the message byte to be transmitted. Bit[13] must be
HIGH for Message Mode to ensure that the output channel is not tri-stated.
The Control Register bits MS[2:0] must be set to 000 to select the Local Connection Memory for the write and read
operations via the microprocessor port. The Control Register bits MS[2:0] must be set to 001 to select the
Backplane Connection Memory for the write and read operations via the microprocessor port. See Section 6.0,
Microprocessor Port, and Section 13.1, Control Register (CR) for details on microprocessor port access.
8.3
This feature allows fast, simultaneous, initialization of the Local and Backplane Connection Memories after
power-up. When the Memory Block Programming mode is enabled, the contents of the Block Programming
Register (BPR) will be loaded into the connection memories. See Table 11 and Table 12 for details of the Control
Register and Block Programming Register values, respectively.
Local Connection Memory
Backplane Connection Memory
Connection Memory Block Programming
Connection Memory
Source Stream Bit Rate
Table 2 - Local and Backplane Connection Memory Configuration
32 Mbps
Zarlink Semiconductor Inc.
Source Stream No.
legal values 0:7
ZL50052
Bits[12:9]
25
Source Channel No.
legal values 0:511
Bits[8:0]
Data Sheet