MK50H28N ST Microelectronics, Inc., MK50H28N Datasheet - Page 46

• Manufacturer Part Number: MK50H28N
• Description: Multi Logical Link Frame Relay Controller
• Manufacturer: ST Microelectronics, Inc.

MK50H28
4.4.2.1 User Mode (Auto LMI Mode) - Continued
In User Mode the MK50H28 will perform the following functions:
4.4.2.2 Network Mode (Auto LMI Mode)
The following procedure should be followed for establishing a link.
In Network Mode the MK50H28 will perform the following functions:
4.4.2.3 Bi-directional Procedures (Auto LMI Mode)
The following procedure should be followed to implement the Optional Bi-directional Procedures
In Bi-directional Mode the MK50H28 will perform the following functions:
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1. Transmit STATUS ENQUIRY frames at an interval determined by the nT1 timer.
2. After every nN1 transmissions of STATUS ENQUIRY with Report Type of "LIV Only" the
3. When a STATUS frame is received in response to a STATUS ENQUIRY, the receive sequence
4. A received Full STATUS frame will be stored into the LMI channel buffer, the sequence number
5. A received Asynchronous STATUS frame will be stored into the LMI channel buffer and its recep-
6. An available transmit or receive buffer is not required for the MK50H28 automatic processing of
7. A STATUS ENQUIRY frame (Full or LIV only) received in User mode will be discarded and the
1. Make sure that the ACTIVE bit in the ALT is set for the LMI channel.
2. Issue the Auto LMI Primitive 7 with UPARM = 1 through CSR1 (write 5700H) to place the device
1. Automatically responds to STATUS ENQUIRY with Report Type of "LIV Only" by transmitting a
2. When a STATUS ENQUIRY with Report Type of "Full Status" is received, the device issues the
3. An available transmit or receive buffer is not required for the MK50H28 automatic processing of
4. Asynchronous STATUS frames may be transmitted by placing the data to be transmitted into the
5. A STATUS frame (Full, LIV Only, or Asynchronous) received in Network mode will be discarded
1. Make sure that the ACTIVE bit in the ALT and TXRDY in the CT are set for the LMI channel.
2. Make sure that the Transmit Ring Pointer, Current Transmit Descriptor and address field informa-
3. Issue the Auto LMI Primitive with UPARM = 2 through CSR1 (write 6700H) to place the device in
1. The MK50H28 supports this operation using separate User and Network sequence numbers and
2. The MK50H28 transmits STATUS ENQUIRY messages with a User set of sequence numbers at
MK50H28 transmits a STATUS ENQUIRY with Report Type of "Full Status".
number received from the Network side is checked against the User send sequence number.
checking will be performed, and its reception will be indicated via Provider Primitive 13.
tion will be indicated via Provider Primitive 14.
"LIV only" frames.
Discarded Frames Counter in Context Table entry 0 will be incremented.
in Auto LMI Network Mode.
STATUS frame with Report Type of "LIV Only" along with restarting the nT2 timer.
LMI Received primitive 13 (with PPARM=1) and expects the host to respond with an LMI Status
Request Primitive 11 with UPARM=0 (when ready to transmit the Full STATUS frame).
"LIV only" frames.
appropriate buffer and issueing Primtive 11 with UPARM=2.
and the Discarded Frames Counter in Context Table entry 0 will be incremented.
tion in the CT is valid. This is necessary for transmission of Full STATUS frame.
Bi-directional Mode. In Bi-directional Mode the MK50H28 will transmit STATUS ENQUIRY
frames with one set of sequence numbers and use a separate set of sequence numbers to proc-
ess received STATUS ENQUIRY frames. STATUS frames will be sent with the separate set of
sequence numbers differing from those used in the processing of recived STATUS frames.
N392 and N393 counters.
an interval determined by the nT1/T391 timer. The expected response is a STATUS frame with
corresponding sequence numbers.