TXC-05802AIPQ Transwitch Corporation, TXC-05802AIPQ Datasheet - Page 29

• Manufacturer Part Number: TXC-05802AIPQ
• Manufacturer: Transwitch Corporation

Specifications of TXC-05802AIPQ

• Operating Supply Voltage (typ): 3.3/5V
• Operating Temperature Classification: Industrial
• Package Type: PQFP
• Mounting: Surface Mount
• Pin Count: 208
• Lead Free Status / Rohs Status: Not Compliant

VCI Translation Record Formats
VCI translation records are six bytes long if TRHENA=0, and eight bytes long if TRHENA=1, as shown in
Figure 21. Each VCI may be either idle or busy.
The calculation of the start address for the VC record uses information from the VP table addressed by the VP
of the incoming cell, as well as information of the VCI of the incoming cell. The information required from the
VP record is the VCI Page Offset (VPO). In the case with no Tandem Header Translation (control bit
TRHENA=0 in register 0AH) and in UNI mode (control bit UNI=1 in register 0AH) the start address of the VC
record corresponding to an incoming VP/VC, assuming a given number of VCI records per page (VRP, deter-
mined by the control bits VRPS1 and VRPS0 in register 0EH) is calculated (in decimal format) as follows:
or with TRHENA=1 and UNI=1:
or with TRHENA=0 and UNI=0:
or with TRHENA=1 and UNI=0:
5
4
3
2
1
0
5
4
3
2
1
0
VPI and VCI Translation,
TRHENA=0
IDLE VCI, TRHENA=0
CellBus Bus Routing Header MSB
CellBus Bus Routing Header LSB
A
A
1
0
-
-
E
E
E
E
VCI, 8 MSB
VCI, 8 LSB
VPI, 8 LSB
1/0
1/0
I
I
VPI, 4 MSB
VC_Start_Address = 24576 + VPO x VRP x 8 + VCI x 8.
VC_Start_Address =16384 + VPO x VRP x 6 + VCI x 6
VC_Start_Address = 1024 + VPO x VRP x 6 + VCI x 6
VC_Start_Address = 1536 + VPO x VRP x 8 + VCI x 8
Figure 21. VCI Translation Record Formats
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
VPI and VCI Translation,
TRHENA=1
IDLE VCI, TRHENA=1
CellBus Bus Routing Header MSB
CellBus Bus Routing Header LSB
A
A
1
0
Tandem Routing Header MSB
Tandem Routing Header LSB
-
-
E
E
E
E
VCI, 8 MSB
VCI, 8 LSB
VPI, 8 LSB
1/0
1/0
I
I
VPI, 4 MSB
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If the VCI is inactive (A=0) and not
Ignore (I=0), then cells arriving bear-
ing that VCI number are discarded
and counted as misrouted. If I=1,
they are discarded and not counted
as misrouted.
If the VCI is active (A=1), then the VPI
and VCI numbers to be inserted in the
cell, and the CellBus Bus Routing
Header to be used, are read from the
VCI translation record at the positions
indicated.
Ed. 3, November 1999
TXC-05802
CUBIT- Pro
TXC-05802-MB