AM79C970A Advanced Micro Devices, AM79C970A Datasheet - Page 28

• Manufacturer Part Number: AM79C970A
• Description: PCnet-PCI II Single-Chip Full-Duplex Ethernet Controller for PCI Local Bus Product
• Manufacturer: Advanced Micro Devices

operates in the same signaling environment as the PCI
bus interface.
TDI
Test Data In
TDI is the test data input path to the PCnet-PCI II con-
troller. The pin has an internal pull-up resistor. The TDI
input operates in the same signaling environment as the
PCI bus interface.
TDO
Test Data Out
TDO is the test data output path from the PCnet-PCI II
controller. The pin is tri-stated when the JTAG port is in-
active. The TDO output operates in the same signaling
environment as the PCI bus interface.
TMS
Test Mode Select
A serial input bit stream on the TMS pin is used to define
the specific boundary scan test to be executed. The pin
has an internal pull-up resistor. The TMS input operates
in the same signaling environment as the PCI
bus interface.
Test Interface
NOUT
NAND Tree Out
When RST is asserted, the results of the NAND tree
testing can be observed on the NOUT pin.
Note that the NOUT pin is multiplexed with the
DXCVR pin.
Power Supply Pins
AV
Analog Power (4 Pins)
There are four analog +5 V supply pins. Special atten-
tion should be paid to the printed circuit board layout to
28
DD
AMD
P R E L I M I N A R Y
Output
Output
Power
Input
Input
Am79C970A
avoid excessive noise on these lines. Refer to
Appendix B and the PCnet Family Board Design and
Layout Recommendations application note (PID
#19595A) for details.
AV
Analog Ground (2 Pins)
There are two analog ground pins. Special attention
should be paid to the printed circuit board layout to avoid
excessive noise on these lines. Refer to Appendix B and
the
Recommendations application note (PID #19595A)
for details.
V
Digital Power (6 Pins)
There are six power supply pins that are used by the in-
ternal digital circuitry. All V
a +5 V supply.
V
I/O Buffer Power (4 Pins)
There are four power supply pins that are used by the
PCI bus input/output buffer drivers. In a system with 5 V
signaling environment, all V
to a +5 V supply. In a system with 3.3 V signaling
nvironment, all V
+3.3 V supply.
V
Digital Ground (12 Pins)
There are 12 ground pins that are used by the internal
digital circuitry.
V
I/O Buffer Ground (8 Pins)
There are 8 ground pins that are used by the PCI bus in-
put/output buffer drivers.
DD
DDB
SS
SSB
SS
PCnet
Family
DDB
pins must be connected to a
Board
DD
DDB
pins must be connected to
pins must be connected
Design
and
Ground
Ground
Power
Layout
Power
Power