peb3456e Infineon Technologies Corporation, peb3456e Datasheet - Page 67

• Manufacturer Part Number: peb3456e
• Description: Channelized T3 Termination, With Ds3 Framer, M13 Multiplexer, T1/e1 Framers And 256-channel Hdlc/ppp Controller
• Manufacturer: Infineon Technologies Corporation

descriptor to the next transmit descriptor. Therefore all information in the next descriptor
must be valid when the data management unit branches to a descriptor. The last
DWORD of a transmit descriptor optionally is written by the TE3-CHATT when
processing of a descriptor has finished.
Table 4-2
FE
HOLD
Data Sheet
DWORD
DWORD
ADDR.
ADDR.
0C
0C
00
04
08
00
04
08
H
H
H
H
H
H
H
H
FE HOLD THI CEN
31
15
0
0
Transmit Descriptor Structure
Frame end
It indicates that the current transmit data section (addressed by transmit
data pointer) contains the end of a frame. After the last byte is read from
system memory this bit is passed to the transmit buffer and to the
protocol machine. The bit FE informs the transmit buffer to move a
stored frame to the protocol machine even if the programmed transmit
forward threshold is not reached (see
Page
(HDLC, PPP) and then to send the interframe time-fill. Providing a
transmit descriptor with FE = ’0’ and HOLD = ’1’ is an error.
Hold indication
It indicates that this descriptor is the last valid element of a linked list.
0
1
30
14
C
0
29
13
74). The protocol machine is informed to append the checksum
0
0
Next descriptor is available in the shared memory. The data
management unit branches to the next descriptor as soon as
processing of the current descriptor has finished.
The current descriptor is the last descriptor containing valid data
in the data section. As soon as the data management unit has
transferred the data contained in the data section to the internal
buffer, it tries one more time to read the descriptor. In case that
28
12
0
0
NextTransmitDescriptorPointer(31:2)
27
11
0
0
0
NextTransmitDescriptorPointer(31:2)
26
10
0
0
0
TransmitDataPointer(31:0)
TransmitDataPointer(31:0)
25
0
0
9
0
67
NO(15:0)
24
0
0
8
0
23
0
0
7
0
22
0
0
6
0
“Internal Transmit Buffer” on
21
0
5
0
Functional Description
20
0
4
0
DescriptorID(5:0)
19
0
3
0
18
0
2
0
PEB 3456 E
17
0
1
0
0
05.2001
16
0
0
0
0