RS232 Commands
8
RS232 Commands
The firmware provided on the unit provides the ability to modify the Evaluation board’s operation through
the RS232 interface. The following instructions assume that you are connected to the RS232 interface and
are using HyperTerminal as described above.
Entering ‘help’ will provide a list of instructions. Note that with the default Hyper-terminal settings, your
typing will not be visible. To see your typing, chose the File>Properties on the menu; then select the
‘Settings’ tab. Press the ‘ASCII Setup...’ button, then check the box to the left of ‘Echo typed characters
locally’, and finish by pressing ‘OK’ twice.
There are 3 basic commands that can be issued through the RS232 interface -”help”, “set”, and “get” (do
not include quotes). The “help” command returns a list of commands. “get” retrieves the current value of a
parameter, and “set” command allows for changing a parameter. Some commands require one or two
parameters, for example “set T 250”, which would set the T parameter to 250. Parameters should be
separated by a space. Care must be taken in changing the Arc Detect parameters (B, D, F, I, C, T) as the
Arc Detect routine does not validate the settings, and these settings may not support proper operation. No
indication is given if the RD-195 is configured with invalid settings.
9
Complete List of RS232 Commands
Command
Default
Name
Usage
Parameter
set/get Arc Detect Parameter ‘B’. set requires a 2nd parameter
B
30.0e3
Analysis Bandwidth
which must be a number greater than 1.0 for proper operation. Note
that the Arc Detection routine is re-initialized after a set command.
Bin Discard Factor: Controls how
set/get Arc Detect Parameter ‘D’. set requires a 2nd parameter
aggressive the filtering is and
which must be a number be between [0.0, 1.0] for proper operation.
D
0.35
corrects for the arc signature
Note that the Arc Detection routine is re-initialized after a set
shaping
command.
Filter Weight: Controls how
set/get Arc Detect Parameter ‘F’. set requires a 2nd parameter
aggressive the filtering is and
F
4.00
which must be a number greater than 0.0 for proper operation. Note
corrects for the arc signature
that the Arc Detection routine is re-initialized after a set command.
shaping.
set/get Arc Detect Parameter ‘I’. set requires a 2nd parameter which
I
45.0e3
Min Frequency
must be a number greater than 1.0 for proper operation. Note that
the Arc Detection routine is re-initialized after a set command.
Clipping Factor: Used to reduce the
set/get Arc Detect Parameter ‘C’. set requires a 2nd parameter
C
55
effect of quick transients causing
which must be a number greater than 1.0 for proper operation.
false detects.
Threshold for arc detection:
Increasing this value reduces the
Sets Arc Detect Parameter ‘T’ to provided number. set requires a
T
250
likelihood of false detections.
2nd parameter which must be a number greater than 1.0 for proper
However, if it is too high, then there operation.
may be a risk of missing an arc.
set/get the unit specific gain correction. This value is in dB, and
U
0.0
Unit Specific Gain Correction
should nominally be 0.0. set requires a 2nd parameter which is the
desired correction for customers.
“get A” returns the string “Arc Detected” or “No Arc Detected” based
A
NA
Arc Detected Status
on current status. “set A” will clear an Arc if an Arc has been
detected and the Arc Automatic clear is disabled.
“set N 1” will enable periodic RS232 notifications on Arc Detected
Status (e.g. “No Arc Detected”).
Periodic RS232 Notifications
“set N 0” will disable periodic notifications on the arc detect status.
N
1 (On)
Enable
“get N” will return the string “Notifications On” or “Notifications Off”
based on the current setting. The default setting is notifications
enabled.
“set R 1" will enable arc detection.
“set R 0" will disable arc detection.
“get R” will return the string “Arc Detect Running” or “Arc Detect not
R
1 (On)
Arc Detection Enable
Running” based on the current setting. The default setting is arc
detection enabled.
Note when arc detection is disabled, the Green LED will turn off and
the Yellow LED will rapidly blink.
5
SNOA564F – June 2011 – Revised December 2012
AN-2154 RD-195 DC Arc Detection Evaluation Board
Copyright © 2011–2012, Texas Instruments Incorporated
