Sun Microsystems SPARCstation 20, Service Manual

Page: 43 / 266

Chapter 19
Abbreviated Diagnostic Mode
POST is executed if the keyboard is disconnected and the
diag-switch?
NVRAM
parameter is set to false in the OpenBoot PROM. During the abbreviated diagnostics,
no progressive test messages are displayed and are not printed. If errors occur
during the abbreviated POST, error messages are transferred through serial port A
and are viewed by connecting a terminal or
tip
connection. If no errors occur, a
message similar to
CODE EXAMPLE 3-2
is displayed through serial port A.
Setting Up a
tip
Connection
The
tip
connection allows the use of a shell window on the Sun Workstation™™ as
a terminal to the system being tested. In setting up a
tip
connection, serial port A is
used to connect to another Sun Workstation (either the same type of SPARC system
or a different type of Sun Workstation or server system). The
tip
connection uses
the SunOS™™ to help in working with the OpenBoot PROM.
To set up a
tip
connection, proceed as follows:
1. Connect the SPARCstation 20 serial port A to another Sun Workstation serial port
using a serial connection cable. This connection is made with a 3-wire null
modem cable. Connect wires 3-2, 2-3, and 7-7.
2. At the other Sun Workstation, add the following line to the
/etc/remote
file:
CODE EXAMPLE 3-2
Typical Abbreviated POST Error-Free Message
SMCC SPARCstation 10/20 UP/MP POST version 3.1 (11/19/93)
CPU_#0 TI, TMS390Z55(3.x) 1Mb External cache
CPU_#1 ******* NOT installed *******
CPU_#2 ******* NOT installed *******
CPU_#3 ******* NOT installed *******
>>>>> Power On Self Test (POST) is running .... <<<<<