EPS RS 232, Manual

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Universal interface (Option)
14
UNIVERSAL INTERFACE (OPTION)
All interfaces of the digital interface are equal. There is no shift between the interfaces. For example, the first
command can be issued via the IEEE interface while the second command can be issued via the RS232 interface. The
return values will be sent from that interface the command was issued from.
C
OMMANDS
Communication is based on an ASCII protocol. The following chapters describe how to write a command and give an
overview over the commands.
Format
A command consists of the command word, a parameter (if necessary) and a terminator. The character for the
terminator is Carriage Return
<CR>
or Line Feed
<LF>
.
Character ASCII Dec value Hex value
Carriage Return <CR> 13 0d
Line Fee <LF> 10 0a
If the command contains a <DEL> or <ESC> character, it will not be processed. Therefore, a command can be cancelled
while entering. Though, a terminator (
<CR>
or
<LF>
) is necessary.
Character ASCII Dec value Hex value
Escape <ESC> 27 1b
Delete <DEL> 127 7f
Commands are not case sensitive and may be mixed up. Therefore, the effect of the following commands is the same:
GTL, Gtl, gTL. Decimal places are optional and separated by a full stop ‘
. ‘ . The number of decimal places is not limited.
Therefore, the effect of the following commands is the same: UA,10, UA,10.0, UA,10.000000000, UA,0010,
UA,010.0000
The number of decimal places to be analyzed depends on parameter and unit type. It corresponds to the number of
decimal places, a command without a parameter would return. As a rule, decimal places are analyzed until a
resolution of 0.1% is reached.
Example: Evaluation of decimal places
EPS/MP with 600 V, 25 A
600 V * 0.1 % = 0.6 V
one decimal place
25 A * 0.1 % = 0.025 A three decimal places
Optional, after a numerical value, a letter may be added to indicate the unit. However, this letter will not be analyzed.
Example: Attached letter as unit
UA,10.0 V
Resets output voltage to 10 V
UA,10.0 m Caution! The ‚m‘ will not be evaluated, output voltage here is also 10 V
Example: A valid command with corresponding hex values
U
A , 1 0 . 2 <CR>
55 h 41 h 2 ch 31 h 30 h 2 eh 32 h 0 dh
Example: Adjustment of output voltage 10 V/5 A (full command sequence)
OVP,100
adjusts OVP to 100 V
UA,10 adjusts output voltage to 10 V
IA,5 current limiting 5 A
SB,R output enabled