XITRON XT2640, Operating Manual

Page: 139 / 187

XT2640 Operating Manual 13 July 2016 Page 139 of 187
24.2.2 FIELDS WITHIN A COMMAND
Command fields are one of the types described below. In certain cases a single field may be formed by multiple sub‐fields, in which
case each successive sub‐field (each having one of the field types described below) is separated from the previous by a preceding
sub‐field separator character.
24.2.2.1 KEYWORD COMMAND FIELD SYNTAX
A KEYWORD field is a combination of printable ASCII characters which match the corresponding allowable keywords as described
later. A KEYWORD field is not case‐sensitive (e.g. the letters V and v are equivalent) and may be preceded and/or followed by one or
more whitespace characters but may not contain any whitespace characters within it.
Examples of valid KEYWORD fields are –
*CLS
*cls
*Cls
ARANGE
Arange
CH1
Ch1
ch1
24.2.2.2 STRING COMMAND FIELD SYNTAX
A STRING field is any combination of any printable ASCII characters in the range ‘space’ through ‘z’. A STRING field is literal,
containing the exact definition of the required string; however certain characters have special meaning –
! The Ω character
\ The ø character
$ The µ character
^ The Σ character
[ The up arrow character
` The down arrow character
] The ° character
‘ The centre dot character
Note that STRING fields are only terminated by a command terminator or separator character and may contain what would normally
be any other separator character (if printable).
Examples of valid STRING fields are –
This is a string field
Volts:
24.2.2.3 NR1 COMMAND FIELD SYNTAX
A NR1 field is any combination of ASCII numeric (0 through 9) characters which form an integer value. A NR1 command field must
not include a polarity character. A NR1 field may be preceded and/or followed by one or more whitespace characters but may not
contain any whitespace characters within it.
All NR1 fields must be in the range 0 to 4294967295 and will cause a syntax error if outside of this range and in most commands this
range is further limited and will cause a data range error if that range is exceeded.
Examples of valid NR1 fields are –
10
153465782
24.2.2.4 NR3 COMMAND FIELD SYNTAX
A NR3 field is any combination of ASCII characters which form a floating point value. A NR3 field may be preceded and/or followed
by one or more whitespace characters but may not contain any whitespace characters within it.
All NR3 fields are decoded and used within the XT2640 with approximately 1 in 10
7
resolution and may be in the range ‐10
+99
to
10
+99
and may contain a number of characters which is only limited by the maximum length of a command set.
Examples of valid NR3 fields are –
10
10.0
+10.0
1e1
‐10.0
+1.26
+1.26
+1.2345678e‐6