Tektronix Webcam 070-8030-01 User Manual

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Installation
2–10
1780R-Series Service Manual
The rear-panel SERIAL interface connector is a 9-pin, sub-miniature, D-type
connector. It is used as an RS422A or RS232D interface to the 1780R-Series
microcontroller, drivers for both interfaces are resident. RS422A is a balanced
voltage digital interface, while RS232D is a serial binary data interchange.
Figure 2–5 shows the rear-panel SERIAL connector pin assignments.
Figure 2–5: Serial interface connector showing the function of each pin
1780R-Series instrument configurations can be stored at (and retrieved from) a
remote location by connecting a host computer to the rear-panel SERIAL port
that supports RS-232 or RS-422 standards. Because RS232D calls for a 25-pin
connector, a special 9-pin to 25-pin adapter cable will be required to access this
operating mode, unless some form of 9-pin to 9-pin interface is being used.
All front-panel controls are operative in their usual manner when serial remote
operation is employed, which allows local modification when desired. Front-pan-
el LED indicators show current switch settings, even when serial remote control
is used.
Serial Data Format. 8 data bits, 1 stop bit, no parity.
Baud Rates. 300, 1200, 9600, 19200. The baud rate selection is made through
page 3 of the touch screen Configure menu.
The data stream transmitted to and from the host (representing the current
1780R-Series settings) consists of 512 bytes, followed by a one-byte checksum.
All data bytes are in the range of Hex 20 to Hex 7F, so that they are printable
ASCII characters.
In order to use the SERIAL interface with an RS232D compatible host computer
that has a standard RS232D 25-pin connector, an adapter will be required. Both
connectors are the sub-miniature D-type and should be readily available from
most local electronic supply outlets. The adapter connects pin 2 to 2 and pin 3 to
3 of the connectors along with providing a common signal ground between pin 5
SERIAL Interface
Connector
Serial Remote Information
25-Pin to 9-Pin RS232D
Adapter