AOIP OM 17 - D. CONFIGURATION AND OPERATION COMMANDS USING THE RS232 SERIAL LINK; D.1 Introduction

RS 232 CONNECTIONS D
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D. CONFIGURATION AND OPERATION COMMANDS USING THE RS232 SERIAL
LINK
This section provides the syntax used for configuration and operation commands using the RS232 serial link
on the OM 17 microhmmeter.
D.1 Introduction
 Commands and their arguments are sent in ASCII code, without a checksum and end with the <LF>
character (10 in decimal notation or 0x0A in hexadecimal notation), or the <CR><LF> pair (OxOD0A).
These commands do not all necessarily receive a reply. As a general rule, the commands that generate a
reply by the unit end with a question mark.
 Arguments are separated by commas.
 For numerical arguments, the separator between the decimals is a decimal point.
 If the arguments are incorrect, the unit sets the error code ERR_NO (see ERR_NO? and ERR?) and does
not reply, if a reply was expected.
 Some commands are only accepted if the unit is in "Remote" mode, as shown in the detailed description
(section 4.2).
 Depending on the commands used, the unit uses two types of replies:
In the case of "short" replies, the data is sent in ASCII mode and ends with <CR><LF>.
Longer replies are sent in the form of binary data blocks with a set size, using the following general format:
#YXX<binary data> <LF>
Y, XX are ASCII characters.
Y = digit between ‘1’ and ‘9’ indicating the number of digits that make up number XX.
XX = is an ASCII number (that can comprise 1 to 9 digits) giving the size in bytes of the <binary data>
that follows (not including the terminator <LF>).
<binary data> = a succession of XX bytes that can take any value between 0 and 255.
Example of a reply of this kind: #15 0x04 0x03 0x0A 0x15 0x16 <LF>
The <binary data> sent can encode integer or floating point numbers comprising more than one byte. For
this kind of data, the bytes are sent "MSB" first.
 Replies in the form of blocks of undefined size are not used in this version, but could be in the future.
These blocks only comprise ASCII characters and their general form is as follows:
#0<CR><LF>
<succession of ASCII characters><CR> <LF>
<succession of ASCII characters> <CR><LF>
…
<LF>
In this case, the end of the reply is detected by receiving a blank line.
Example of a reply of this type:
#0<CR><LF>
REPLY LINE 1<CR><LF>
REPLY LINE 2<CR><LF>
LAST REPLY LINE<CR><LF>
<LF>
 Communication: - Speed: 4800, 9600, 19200 or 31250 baud.
- One stop bit, no parity.