Manual

DS31256
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3. SIGNAL DESCRIPTION
3.1 Overview/Signal List
This section describes the input and output signals on the DS31256. Signal names follow a convention
that is shown in the Signal Naming Convention table below. Table 3-A
lists all of the signals, their signal
type, description, and pin location.
Signal Naming Convention
FIRST LETTER SIGNAL CATEGORY SECTION
R Receive Serial Port 3.2
T Transmit Serial Port 3.2
L Local Bus 3.3
J JTAG Test Port 3.4
P PCI Bus 3.5
Table 3-A. Signal Description
PIN NAME TYPE FUNCTION
V19 JTCLK I JTAG IEEE 1149.1 Test Serial Clock
U18 JTDI I JTAG IEEE 1149.1 Test Serial Data Input
T17 JTDO O JTAG IEEE 1149.1 Test Serial Data Output
W20 JTMS I JTAG IEEE 1149.1 Test Mode Select
U19
JTRST
I JTAG IEEE 1149.1 Test Reset
G20 LA0 I/O Local Bus Address Bit 0, LSB
G19 LA1 I/O Local Bus Address Bit 1
F20 LA2 I/O Local Bus Address Bit 2
G18 LA3 I/O Local Bus Address Bit 3
F19 LA4 I/O Local Bus Address Bit 4
E20 LA5 I/O Local Bus Address Bit 5
G17 LA6 I/O Local Bus Address Bit 6
F18 LA7 I/O Local Bus Address Bit 7
E19 LA8 I/O Local Bus Address Bit 8
D20 LA9 I/O Local Bus Address Bit 9
E18 LA10 I/O Local Bus Address Bit 10
D19 LA11 I/O Local Bus Address Bit 11
C20 LA12 I/O Local Bus Address Bit 12
E17 LA13 I/O Local Bus Address Bit 13
D18 LA14 I/O Local Bus Address Bit 14
C19 LA15 I/O Local Bus Address Bit 15
B20 LA16 I/O Local Bus Address Bit 16
C18 LA17 I/O Local Bus Address Bit 17
B19 LA18 I/O Local Bus Address Bit 18
A20 LA19 I/O Local Bus Address Bit 19, MSB
L20
LBGACK
O Local Bus Grant Acknowledge
H20
LBHE
O Local Bus Byte High Enable
J20 LCLK O Local Bus Clock
K19 LCS* I Local Bus Chip Select
V20 LD0 I/O Local Bus Data Bit 0, LSB
U20 LD1 I/O Local Bus Data Bit 1
T18 LD2 I/O Local Bus Data Bit 2
T19 LD3 I/O Local Bus Data Bit 3