MTD658E Datasheet, PDF (15/23 Pages) List of Unclassifed Manufacturers – 5/8 Port 10/100 Hub Build_in Bridge And Memory

MYSON
TECHNOLOGY
MTD658E
5.0 FUNCTIONAL DESCRIPTIONS
The MTD658E is conformed to IEEE802.3 chapter 9 and IEEE802.3u clause 27 specifications. The
MTD658E provides 8 Reduced MII interfaces and an embedded two port switch (build_in 64k8 ASRAM
on chip) to construct a 10M/100M dual speed Hub application. And also, MTD658E can be configured
to 5 port mode, it will provide 4 RMII and 1 MII interface. Two Inter-Bus are also provided for stackable
10M/100M dual speed Hub application. Since MTD658E build_in memory on chip, there are no need
any extra memorys in the application board.The MTD658E functions are described as follows:
5.1 Repeatation and data handling
8 independent RMII ports integrated with IEEE802.3 chapter 9 and IEEE802.3u clause 27 repeater
functions simultaneously. MTD658E embedded two Hub cores (10M and 100M) ,and each dedicated
RMII interface port can get per port’s speed information from per port speed input pin, and then
MTD658E will switch individual port to their appropriated Hub core functions (10M or 100M).
The MTD658E receive packets from each RMII ports, and redirect port’s input packet to 10M or 100M
Hub core according each port’s speed. The internal IEEE802.3 chapter 9 or IEEE802.3u clause 27
repeater main state machine will starts to repeat the input packet to all ports except the input port. If
larger than or equal to two ports have input packet simultaneously, this will be treated as a collision, and
MTD658E will assert an arbitrary JAM pattern to all ports’output until collision event disappear and net-
work is idle.
5.2 Partition
The MTD658E provides 10M/100M auto partition/reconnection functions to guarantee the network seg-
ment performance by means of dectecting a consecutive collisions. Each dedicated RMII port has
implement a individual 10M/100M auto partition/reconnection state machine. If port’s consecutive colli-
sion number over or equal to CClimit (10M CClimit default is 32, 100M CClimit default is 64), this port
will be partitioned. Reconnection will occurs after a larger than 512 bit time packet was received or
transmitted from this partitioned port without any collision.
When port is under partition state, MTD658E will not accept any input messages from this port (just
monitor input message), but will continue output repeated messages to this partition port.
Some new partition criterions are also implement, such as long_collision_partition event,
jabber_partition event. In 10M/100M partition state machine, longer than 1024 bit time continueous col-
lision will force port enter partition state. In 100M partition state machine, if port enter jabber_on state,
this port will be partitioned. In 10M, jabber_partition function is not implemented.
5.3 Jabber
The jabber protect function is used to prevent an illegally long packet reception. After the MTD658E
received a longer than 65536 +/- 6.25% bit times packet, this receive port‘s receive/transmit path will be
inhibited until carrier is no longer detected.
5.4 MII Setting
Due to HUB is an half duplex device, the MTD658E need to force all connected phsical devices to work
in half duplex environment. The MTD658E will setting all PHY’s SMI register 4’s half/full duplex bit dur-
ing power on, and than restart auto-negotiation procedure to work in half duplex mode. In 8 port mode,
the PHY’s device ID should be setted from 5h04 - 5h0b (port0-7) or from 5h08 -5h0f (port0-7); In 5 port
mode, the PHY device ID should be setted from 5h07 - 5h0b (port0-4) or from 5h0b -5h0f (port0-4).
5.5 Inter-Bus Interface
Two Inter-Bus Interface are provided by the MTD658E, One is 10M Inter-Bus Interface, the other is
100M Inter-Bus Interface. The Inter-Bus interface is designed for stackable hub application. For each
domain, up to 4 MTD658Es can be stacked through this Inter-Bus without any external arbitration logic.
The Inter-Bus Interface includes IMASTER, IDATA (100M: use IDAT<3:0>, 10M: use only IDAT),
REQOUT, REQIN0-2, ICLK, IACKB, ICOLB pins. IMASTER decide which MTD658E can arbitrate the
Inter-Bus, and only one MTD658E’s IMASTER can be tie high in a stackable Hub. IDATA are synchro-
15/23
MTD658E Revision 1.1 05/25/2000