IDT72V8985 Integrated Device Technology, IDT72V8985 Datasheet - Page 7

• Manufacturer Part Number: IDT72V8985
• Description: 3.3 Volt Time Slot Interchange Digital Switch 256 X 256
• Manufacturer: Integrated Device Technology

IDT72V8985 3.3V Time Slot Interchange
Digital Switch 256 x 256
The Control Register is only accessed when A5=0.
All other address bits have no effect when A5=0.
When A5 =1, only 32 bytes are randomly accessable
via A0-A4 at any one instant. Which 32 bytes are
accessed is determined by the state of CRb0 -CRb4.
The 32 bytes correlate to 32 channel of one ST-BUS
stream.
Channel 0
Channel 0
Channel 0
Channel 0
Channel 0
Channel 0
Channel 0
Channel 0
100000
Control Register
Connection Memory High
Channel 1
Channel 1
Channel 1
Channel 1
Channel 1
Channel 1
Channel 1
Channel 1
100001
Connection Memory Low
Data Memory
Channel 2
Channel 2
Channel 2
Channel 2
Channel 2
Channel 2
Channel 2
Channel 2
100010
CR
b
Figure 5. Addressing Internal Memories
7

CR
b
CR
6 CR
0
1
1
b
4 CR
b
5 CR
1
0
1
7
b
3
b
4 CR
Channel 31
Channel 31
Channel 31
Channel 31
Channel 31
Channel 31
Channel 31
Channel 31
111111
b
3 CR
b
2 CR
External Address Bits
b
1 CR
CR
0
0
0
0
1
1
1
1
Commercial Temperature Range
b
2 CR
b
0
0
0
1
1
0
0
1
1
b
1 CR
A5-A0
0
1
0
1
0
1
0
1
b
0
Stream
5707 drw08
0
1
2
3
4
5
6
7