MB86967 Datasheet, PDF (84/129 Pages) Fujitsu Component Limited. – LAN Controller with PC Card, ISA Bus, and General-purpose Bus Interfaces

MB86967
Table 6 Control and Status Parameters
Symbol Type
Name
Description
DLC EN
Register DATA LINK
Bit
CONTROL
ENABLE
When high, resets all buffer memory pointers and disables both the
transmitter and the receiver circuits. When low, enables buffer
memory, transmitter and receiver.
LBC
Register LOOPBACK
Bit
CONTROL
When set low, places MB86967 in internal loopback mode.
RBUF
EMPTY
Register RECEIVE
Bit
BUFFER
EMPTY
When high, indicates that there is at least one complete packet
stored in the receive buffer, ready to read. When low, indicates there
are no packets ready to read in the receive buffer.
RPKT
LEFT
Software RECEIVE
Value PACKET
LENGTH LEFT
The number of bytes remaining in the receive packet being read from
the buffer. Calculated by the driver from the original length given by
MB86967 in the 3rd and 4th bytes of the receive packet header, less
the number of bytes already read out.
RX CNT
Software RECEIVE
Value TRANSFER
COUNT
A running count of the number of packets transferred from the
receive buffer to system memory since entering the Receive Packet
Read Routine. This parameter can share the same memory location
with TX CNT, because both are not used concurrently in the same
subroutine.
RX MAX
Software MAXIMUM
The maximum number of packets that may be processed in the
Value VALUE FOR RX Receive Packet Read Routine.before passing control to the Transmit
CNT
Packet Write Routine. This parameter can be fixed or allowed to vary
according to need. Typical range for this parameter is 15 - 32.
TBUF
FREE
Software TRANSMIT
The number of available bytes remaining in the transmit buffer being
Value BUFFER FREE loaded with packets by the driver. Calculated by driver.
SPACE
TBUF
MODE
Register TRANSMIT
The configuration of the transmit buffer space, SINGLE buffer or
Bits
BUFFER MODE DUAL buffers.
TBUF SIZE Software TRANSMIT
The size in bytes of each transmit buffer, which depends on initial
Value BUFFER SIZE configuration parameters for the buffer memory.
TBUF STAT Software TRANSMIT
Value BUFFER
STATUS
Current status of the transmit buffer available for loading packets.
Maintained by the driver.
TBUF STAT
Value Description
Empty
Current transmit buffer available to system bus is
completely empty.
Busy
No buffer is currently available to the system bus
because a) MB86967 is in single-buffer mode and
b) the transmitter is using the buffer.
Standby
The buffer currently available to the system bus has
one or more packets in it, but may still have room for
additional packet(s).
Full
The buffer currently available to the system bus has
one or more packets in it, and does not have room for
the next packet presented to the driver from the
transmit queue.
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