Tektronix SDA601, Service Manual

Page: 26 / 132

Operating Information
2- 4 SDA 601 Serial Digital Analyzer
Connect the instrument to your system through the SERIAL INPUT with 75
Ω
coaxial cable.
NOTE
. The SDA601 has internal, active termination. Any signal path that ends
with the instrument will be properly terminated only when the SDA601 is
switched on.
The AUX output signal may be thought of as “pseudo video.” It is derived from
the serial video input signal and converted to composite monochrome analog
video by an unfiltered 5-bit DAC. It is suitable for identifying the input and
displaying the cursor cross hairs, Highlighting, and the “OSD.” It:
H
Lets you view the picture for convenient source identification.
H
Can contain the On-screen Display (OSD; see page 2--9), which shows the
most recent Watch or Analyze results one page at a time—instead of one
item at a time as on the SDA601 display.
H
With Pulse Cross enabled (see page 2--24), lets you “see” the contents of the
vertical and horizontal interval portions of the serial video signal.
H
Can include Cursor cross hairs for convenient positioning of the Cursors (see
page 2--22).
H
When Highlighting (see page 2--24) is turned on, can help you locate and
identify errors in the picture, or the digital encoding of the signal.
By factory default, the AUX output is the Y (luminance) video component; you
may configure it, through the I/O menu, to be the R–Y or B–Y component
instead. (To access this setting, press
Shift
, then
Insert On/Off
, then Y .)
Connect an ASCII, serial printer to the RS-232 connector to create “hard copy”
analysis reports, or to log errors detected during a Watch session. You may also
capture the RS-232 output on a personal computer running a communications
application such as PROCOMM
R
or the Terminal accessory of Microsoft
R
Windows
T
. With a printer or PC connected, you can choose—through the Alarm
menu—to have the SDA601 log every error as it occurs, or to print a Watch
report every ten seconds. This will permit unattended monitoring of your system.
See page 2--19 for more information.
Connecting to the RS-232 Port. The SDA601 is an RS-232 DCE device. Table
2--1 lists the pin assignments of the connector. The connector pinout has been
chosen to interface directly with an IBM PC/AT 9-pin serial port using a
straight-through cable. Thus, when communicating with a DTE device that has a
male 9-pin (DB9) connector, use a cable that connects pins 2, 3, 5, 7, and 8
SERIAL INPUT
AUX Output
RS-232 Interface