adm6992c Infineon Technologies Corporation, adm6992c Datasheet - Page 24

• Manufacturer Part Number: adm6992c
• Description: Two Port Bridge Fiber To Fast Ethernet Converter
• Manufacturer: Infineon Technologies Corporation

algorithm is implemented inside the NINJA C/CX (ADM6992C/CX) to prevent the back pressure function causing
HUB partition under a heavy traffic environment and reduce the packet lost rate to increase the whole system
performance.
3.4.10
When a full duplex port runs out of its received buffer space, a PAUSE packet command will be issued by the
NINJA C/CX (ADM6992C/CX) to notify the packet sender to pause transmission. This frame based flow control is
totally compliant to IEEE 802.3x. The NINJA C/CX (ADM6992C/CX) can issue or receive pause packets.
3.4.11
NINJA C/CX (ADM6992C/CX) supports hardware-based bandwidth control for both ingress and egress traffics.
Ingress and egress rates can be limited independently on a per port base. The NINJA C/CX (ADM6992C/CX) uses
8ms at the scale, and the minimum bandwidth control unit is 4 kbit/s so users can configure the rate equal to K *
4 kbit/s, 1<=K<=25000. The NINJA C/CX (ADM6992C/CX) maintains two counters (input and output) for each
port. For example, if users want to limit the rate to 64 kbit/s, they should configure the bandwidth control threshold
to 16. For each time unit, the NINJA C/CX (ADM6992C/CX) will add 64 to the counter and decrease the byte length
when receiving a packet during this period. When the counter is decreased to zero, we can divide the control
behavior into two parts:
1. For the ingress control, the ingress port will not stop receiving packets. If flow control is enabled, Pause packets
2. For the egress control, the egress port will not transmit any packets. The port receiving packets that are
3.4.12
With the use of external CPU support, the NINJA C/CX (ADM6992C/CX) can issue an interrupt to the CPU if any
event defined in SMI interrupt register 10
3.4.13
The normal application in which a Switch connects to a NIC card is by a one-to-one TP cable. If the Switch
connects to other devices such as another Switch, it can be done by two ways. The first is to use a Cross Over TP
cable and the second way is to use an extra RJ45 connector by internally crossing over the TXP/TXN and
RXP/RXN signals. By using the second way, customers can use a one-to-one cable to connect two Switch
devices. All these efforts add extra costs and are not a good solution. The NINJA C/CX (ADM6992C/CX) provides
an Auto MDIX function, which adjusts the TXP/TXN and RXP/RXN automatically on the correct pins. Users can
use one-to-one cabling between the NINJA C/CX (ADM6992C/CX) and other devices either switches or NICs.
3.5
3.5.1
The NINJA C/CX (NINJA C/CX (ADM6992C/CX)) Media Converter incorporates a Fault Propagation feature,
which allows indirect sensing of a Fiber Link Loss via the 10/100Base-TX UTP connection. Whenever the NINJA
C/CX (NINJA C/CX (ADM6992C/CX)) Media Converter detects a Link Loss condition on the Received fiber (Fiber
LNK OFF), it disables its UTP link pulse so that a Link Loss condition will be sensed on the UTP port to which the
Data Sheet
will be transmitted, if Back Pressure is enabled, Jam packets will be transmitted, and if the above functions are
not enabled, the packet will be discarded.
forwarded to the egress port will transmit Pause packets if flow control is enabled, transmit Jam packets if Back
Pressure is enabled, and discard packets if all the above functions are not enabled.
Full Duplex Flow Control
Bandwidth Control
Interrupt
Auto TP MDIX function
Converter Functional Description
Fault Propagation
H
and SMI interrupt mask register 11
24
H
occurs.
Function Description
Rev. 1.02, 2005-11-25
ADM6992C/CX
Ninja C/CX