TI380C25 Datasheet, PDF (15/71 Pages) Texas Instruments – TOKEN-RING COMMPROCESSOR

TI380C25
TOKEN-RING COMMPROCESSOR
SPWS012 – JANUARY 1995
Pin Functions (Continued)
PIN
NAME
NO.
TEST0
103
TEST1
102
TEST2
101
TEST3
100
TEST4
99
TEST5
98
XFAIL
104
I / O^†
I
I
I
Token-Ring Media Interface
DESCRIPTION
Network select inputs. TEST0 – TEST2 are used to select the network speed and type to be used by
the TI380C25. These inputs should be changed only during adapter reset. Connect TEST2 to VDDL.
TEST0
L
H
X
TEST1
NC
NC
X
TEST2
H
H
L
DESCRIPTION
16-Mbps token ring
4-Mbps token ring
Reserved
Test inputs. TEST3 – TEST5 should be left unconnected (see Note 1). Module-in-place test mode is
achieved by tying TEST3 and TEST4 to ground. In this mode, all TI380C25 outputs are in the
high-impedance state. Internal pullups on all TI380C25 inputs are disabled (except TEST3 – TEST5).
External fail-to-match signal. An enhanced-address-copy-option (EACO) device uses XFAIL to
indicate to the TI380C25 that it should not copy the frame nor set the ARI / FCI bits in a token-ring frame
due to an external address match.The ARI / FCI bits in a token-ring frame can be set due to an internal
address-matched frame. If an EACO device is not used, XFAIL must be left unconnected. XFAIL is
ignored when CAF mode is enabled [see table in XMATCH description (see Note 1)].
H = No address match by external address checker
L = External address-checker-armed state
External match signal. An enhanced-address-copy-option (EACO) device uses XMATCH to indicate
to the TI380C25 to copy the frame and set the ARI / FCI bits in a token-ring frame. If an EACO device
is not used, XMATCH must be left unconnected. XMATCH is ignored when CAF mode is enabled
(see Note 1).
XMATCH
H = Address match recognized by external address checker
105
I
L = External address-checker-armed state
XMATCH
XFAIL FUNCTION
0
0
Armed (processing frame data)
0
1
Do not externally match the frame (XFAIL takes precedence).
1
0
Copy the frame
1
1
Do not externally match the frame (XFAIL takes precedence).
Hi-Z
Hi-Z Reset state (adapter not initialized)
† _{I = input, O = output}
NOTE 1: Pin has an internal pullup device to maintain a high-voltage level when left unconnected (no etch).
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