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Qservice ----- This Document is a complete scan from the Original Tektronix Manual ----- Qservice

CONTENTS
Page

HOST COMMUNICATION . . . . . . . . . . . . . . . . . . . . 1 RS-232 INTERFACE SPECIFICATIONS . . . . . . 1
RS-232 Communications Parameters . . . . . . . . . . . . Baud Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum Applied Voltage (any pin) . . . . . . . . . . . . . . PlotterIPrinter Support . . . . . . . . . . . . . . . . . . . . . . . . . Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 2 2 2 2 2

RS-232 OPTIONAL ACCESSORIES . . . . . . . . . . CODES and FORMATS . . . . . . . . . . . . . . . . . . . . . . . Commands. Queries. and Responses . . . . . . . . . . . . COMMANDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . QUERIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 3 3 8 RESPONSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Logical Front Panel Encoding . . . . . . . . . . . . . . . . . . 11 VERTICAL SETTINGS . . . . . . . . . . . . . . . . . . . . . 11 SECIDIV SETTINGS . . . . . . . . . . . . . . . . . . . . . . 14 TRIG POS. SLOPE. SOURCE. AND MODE SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 ACQUISITION MODE AND MlSC SETTINGS . . 18
20 20 20 23 24 24 24 24 25 25 28

RS-232 ERROR CODES . . . . . . . . . . . . . . . . . . . . . Communication Error Codes . . . . . . . . . . . . . . . . . . . Diagnostic Error Codes . . . . . . . . . . . . . . . . . . . . . . . Error Code Decoding Examples . . . . . . . . . . . . . . . . RS-232 COMMUNICATIONS . . . . . . . . . . . . . . . .
Waveform Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . Software Tools . . . . . . . . . . . . . . . . . . . . . . . . . . Available Software . . . . . . . . . . . . . . . . . . . . . . . Transfer to a Local PC . . . . . . . . . . . . . . . . . . . . Transfer via a Modem . . . . . . . . . . . . . . . . . . . . RS-232 Interconnection Cables . . . . . . . . . . . . . . . .

INDEX

222 RS-232 Interface Guide

RS-232 INTERFACE
HOST COMMUNICATION
Communication between the 222 and an external host computer is provided via an RS-232 communications interface. The actual format of the commands is as close to the Tek Codes and Formats as possible with the limited memory space available. Certain functions are compressed into a more compact form. Waveforms and front-panel settings may be transferred over the RS-232 serial port in ascii character strings. The optional RS-232 Demonstration Disk accessory (available by request only) supports communications with an IBM8 PC AT@or PC compatible computer. Operating details are provided on the disk in a "README" file.
A simple terminal can be used to receive the messages that may be generated at power on or during self calibration if an error occurs. The error codes are defined later in this manual. An RS-232 interconnection cable for use with the 222 is available as an optional accessory. Setting the communication baud rate for the 222 is done using menu selections available in the Auxiliary Functions menu under CONFIG.

RS-232 INTERFACE SPECIFICATIONS
RS-232 Communication Parameters

Start bits Stop bits Data bits Parity Flow Control Signals

1 1 8 None XONIXOFF RX, TX, and SGND are functional. SGND is connected internally to EXT TRIG COMM. DSR and CTS are always high, and DTR and RTS are ignored.

Baud Rates 300,1200,2400,9600; 0.1 % accuracy based on the microprocessor clock.
IBM PC XT and IBM PC AT are registered trademarks of the International Business Machine Corp.

222 RS-232 Interface Guide

Levels Compatible with RS-232C. Maximum Applied Voltage (any pin) 25 V (dc peak ac).

+

PlotterJPrinterSupport There is no plotter support in the instrument. Messages User message displays on the instrument crt are not supported. The controlling PC cannot send messages to be displayed for the operator of the 222.

RS-232 OPTIONAL ACCESSORlES
RS-232 Demo Disk RS-232 Interconnection Cable 063-0070-00 175-1453-00

CODES AND FORMATS
Commands, front panel setups, and waveforms sent over the RS-232 interface are composed of ascii character strings. The ascii characters represent hexadecimal numbers, with two characters per hexadecimal value. (See "Logical Front Panel Encoding" for the meanings of the numbers.) The general command format is as follows: cmd arg:data; where cmd is the command; arg is an argument to the command, and data is any additional data needed for the command. A single white space (either a space or a tab) is needed between the command and argument. There must be no white space on either side of the colon delimiter between the argument and the data. The semicolon is the command terminator, but a carriage return also terminates the command.
NOTE The command is executed as soon as the command terminator is received; multiple commands in a string are executed at the command terminator as they are received. A command can be aborted after it has started execution by sending an ESCAPE character.

222 RS-232 Interface Guide

Commands, Queries, and Responses

I

COMMANDS CURV BUT DAC FP

1

I

QUERIES CURV? ID? TRG? STA? DAC? FP? CAL?

RESPONSES

READY DAC FP XXX; CAL

Figure 1. Commands, Queries, and Responses.

The set of commands and queries sent to the instrument and the responses sent by the instrument are shown in Figure 1. Explanation for each is given in the following text.
COMMANDS. The following commands are supported:

CURV : < wfrm data >

Loads waveform data into the specified 222 reference memory (REF1 -REF4). The wfrm data must be sent as hex-encoded ascii characters.
Note

Waveformsmay be written back to Channel I and Channel 2, but they will be overwritten by the next acquisitions into those memories.

222 RS-232 Interface Guide

is one of the following strings: CH 1 Channel 1 waveform CH 2 Channel 2 waveform REF1 Reference waveform 1 REF2 Reference waveform 2 REF3 Reference waveform 3 REF4 Reference waveform 4

< wfrm data >

is composed of < byte count > < checksum > , defined as follows: Ten ascii characters representing hexadecimal bytes of the front panel settings for the waveform data. See "Logical Front Panel Encoding" for the meaning of the characters. Two ascii character representing the frame number (in hexadecimal) the curve data is taken from. The frame numbers range from 00 for the RO (readout) frame to 06 for the REF4 (reference waveform 4 frame). Four ascii characters representing the data byte count for the waveform data (in hexadecimal).

c fp data >

c frame nr >

< byte count >

In YT mode, each data point is the hexadecimal value (represented by two ascii characters) of the Y-coordinate.
In XY mode, the X- and Y-coordinates are sent as two hexadecimal values (represented by four ascii characters) with the X-coordinate value first, followed by the Y-coordinate value.

222 RS-232 Interface Guide

< checksum >

Two ascii characters representing the hexadecimal twos complement of the modulo 256 checksum of all data bytes and the byte count bytes.
Note

Programmers take note, additional bytes may be added to the data string after the checksum byte. This space is reserved for future expansion.
BUT < button >

Simulates a button press. is one or two ASCII characters that represent a button code. The button codes are as follows: CLEAR Menu ltem 0 Menu ltem 1 Menu ltem 2 Menu ltem 3 OFF Trigger SOURCE Trigger MODE Trigger SLOPE CH 2 Select CH 1 Select AUTO SETUP Front-Panel Setup Menu Trigger Position Menu Auxiliary Functions Menu Display Mode Menu Save Waveform Menu Recall Waveform Menu STOREINONSTORE Acq Mode Menu X I 0 MAG Variable Gain AUTO LVL: PUSH