82596CA Datasheet, PDF (21/76 Pages) Intel Corporation – HIGH-PERFORMANCE 32-BIT LOCAL AREA NETWORK COPROCESSOR

82596CA
STATION DIAGNOSTICS
AND SELF-TEST
The 82596 provides a large set of diagnostic and
network management functions These include inter-
nal and external loopback and time domain reflec-
tometry for locating fault points in the network cable
The 82596 ensures software reliability by dumping
the contents of the 82596 internal registers into sys-
tem memory The 82596 has a self-test mode that
enables it to run an internal self-test and place the
results in system memory
82586 SOFTWARE COMPATIBILITY
The 82596 has a software-compatible state in which
all its memory structures are compatible with the
82586 memory structure This includes all the Action
Commands the Receive Frame Area (including the
RFD Buffer Descriptors and Data Buffers) the Sys-
tem Control Block and the initialization procedures
There are two minor differences between the 82596
in the 82586-Compatible memory structure and the
82586
 When the internal and external loopback bits in
the Configure command are set to 11 the 82596
is in external loopback and the LPBK pin is acti-
vated in the 82586 this situation would produce
internal loopback
 During a Dump command both the 82596 and
82586 dump the same number of bytes however
the data format is different
INITIALIZING THE 82596
A Reset command is issued to the 82596 to prepare
it for normal operation The 82596 is initialized
through two data structures that are addressed by
two pointers the System Configuration Pointer
(SCP) and the Intermediate System Configuration
Pointer (ISCP) The initialization procedure begins
when a Channel Attention signal is asserted after
RESET The 82596 uses the address of the double
word that contains the SCP as a default
00FFFFF4h Before the CA signal is asserted this
default address can be changed to any other avail-
able address by asserting the PORT pin and provid-
ing the desired address over the D₃₁ – D₄ pins of the
address bus Pins D₃ – D₀ must be 0010 i e any
alternative address must be aligned to 16-byte
boundaries All addresses sent to the 82596 must be
word aligned which means that all pointers and
memory structures must start on an even address
(A₀^ezero)
SYSTEM CONFIGURATION POINTER
(SCP)
The SCP contains the sysbus byte and the location
of the next structure of the initialization process the
ISCP The following parameters are selected in the
SYSBUS
 The 82596 operation mode
 The Bus Throttle timer triggering method
 Lock enabled
 Interrupt polarity
 Big Endian 32-bit entity mode
Byte ordering is determined by the LE BE pin
LE BE^e1 selects Little Endian byte ordering and
LE BE^e0 selects Big Endian byte ordering
NOTE
In the following X indicates a bit not checked
82586 mode This bit must be set to 0 in all other
modes
21