GR740-UM-DS, Nov 2017, Version 1.7
32
www.cobham.com/gaisler
GR740
3.4
Complete signal list
The listing below shows all interface signals, sorted by interface. Some of these signals are located on
shared pins as indicated in the table, therefore some physical pins will map to more than one entry in
this table, with the pin name taken from the primary function of that pin. Section 3.3 and the device
pin assignments in section 40.3 detail the pin sharing.
Table 28.
All external signals, before pin sharing
Name
Usage
Pin sharing
Direction
Polarity
SYS_RESETN
System reset
No
In
Low
SYS_EXTLOCK
External clocks locked (for reset genera-
tion), tie high if unused
No
In
High
SYS_CLK
System clock
No
In
-
MEM_EXTCLOCK
Alternate clock source for SDRAM inter-
face
No
In
-
SPW_CLK
SpaceWire clock
No
In
Low
PROC_ERRORN
Processor 0 error mode indicator
No
Out-Tri
Low
BREAK
Debug Support Unit and watchdog/proces-
sor break signal. See description of boot-
strap signals.
No
In
High
DSU_EN
Debug Support Unit enable signal
No
In
High
DSU_ACTIVE
Debug Support Unit active signal
No
Out
High
PCIMODE_ENABLE
Enables PCI mode. See description of boot-
strap signals
No
In
High
MEM_CLKSEL
Memory interface external clock select sig-
nal
No
In
-
MEM_IFWIDTH
Memory interface width select signal
No
In
-
MEM_CLK_OUT
SDRAM clock output
No
Out
-
MEM_CLK_OUT_DIFF_P
SDRAM clock output (differential)
No
Out
-
MEM_CLK_OUT_DIFF_N
SDRAM clock output (differential)
No
Out
-
MEM_CLK_IN
SDRAM clock input
No
In
-
MEM_WEN
SDRAM write enable
No
Out
Low
MEM_SN[1:0]
SDRAM chip select
No
Out
Low
MEM_RASN
SDRAM row address strobe
No
Out
Low
MEM_DQM[11:0]
SDRAM data mask
See 3.3.2
Out
Low
MEM_DQ[95:0]
SDRAM data and checkbit bus
BiDir
-
MEM_CKE[1:0]
SDRAM interface clock enable
No
Out
High
MEM_CASN
SDRAM column address strobe
No
Out
Low
MEM_BA[1:0]
SDRAM bank address
No
Out
-
MEM_ADDR[14:0]
SDRAM address and chip select 3,2
No
Out
-
JTAG_TCK
JTAG Clock
No
In
-
JTAG_TMS
JTAG Mode select
No
In
-
JTAG_TDI
JTAG Data in
No
In
-
JTAG_TDO
JTAG Data out
No
Out
-
JTAG_TRST
JTAG Reset
No
In
-
ETH0_TXER
Ethernet port 0, Transmit error
No
Out
High
ETH0_TXD[7:0]
Ethernet port 0, Transmitter output data
No
Out
-
ETH0_TXEN
Ethernet port 0, Transmitter enable
No
Out
High
ETH0_GTXCLK
Ethernet port 0, Gigabit clock
No
In
-