IQ80960RM/RN
Evaluation Board Manual
3-7
Hardware Reference
3.9
JTAG Header
The JTAG header allows debugging hardware to be quickly and easily connected to some of the
IQ80960RM/RN processor’s logic signals.
The JTAG header is a 16-pin header. A 3M connector (part number 2516-6002UG) is required to
connect to this header. The pinout for the JTAG header is shown in
. The header and
connector are keyed using a tab on the connector and a slot on the header to ensure proper installation.
Each signal in the JTAG header is paired with its own ground connection to avoid the noise problems
associated with long ribbon cables. Signal descriptions are found in the i960
®
RM/RN I/O Processor
Developer’s Manual, 80960RM I/O Processor Data Sheet and the 80960RN I/O Processor Data Sheet.
describes switch setting options and defaults. These switch settings are sampled at
Primary PCI Reset. See
Table 5-1 “Initialization Modes” on page 5-3
for processor initialization
configurations.
a.
This switch is active for IQ80960RN ONLY.
Table 3-8.
JTAG Header Pinout
Pin
Signal
Input/Output to 80960RM/RN
Pin
Signal
1
TRST#
IN
2
GND
3
TDI
IN
4
GND
5
TDO
OUT
6
GND
7
TMS
IN
8
GND
9
TCK
IN
10
GND
11
LCDINIT#
IN
12
GND
13
I_RST#
OUT
14
GND
15
PWRVLD
OUT
16
GND
Table 3-9.
Switch S1 Settings
Position
Name
Description
Default
S1-1
RST_MODE#
Determines if the processor is to be held in reset.
ON = hold in rest
OFF = allows processor initialization
OFF
S1-2
RETRY
Determines if the Primary PCI interface will be disabled.
ON = allows Primary PCI configuration cycles to occur
OFF = retries all Primary PCI configuration cycles
OFF
S1-3
32BITMEM_EN#
Notifies Memory Controller of the SDRAM width.
ON = Memory Controller utilizes 32-bit SDRAM access protocol
OFF = Memory Contoller utilizes 64-bit SDRAM access protocol
OFF
S1-4
a
32BITPCI_EN#
Determines whether Secondary PCI bus is a 32- or 64-bit bus.
ON = indicates Secondary PCI bus is a 32-bit bus
OFF = indicates Secondary PCI bus is a 64-bit bus
OFF