E
PI
S
ENSOR
2
U
SER
M
ANUAL
D
OCUMENT
305801,
R
EVISION
A
In addition, the Episensor2 outputs a coded range signal to each of the channels' SIGNAL line:
5 pulses for +/-4g range
4 pulses for +/-2g range
3 pulses for +/-1g range
2 pulses for +/-0.5g range
1 pulse for +/-0.25g range
This signal is output at power-ON, following a RESET event, and following any range-setting
activity. Typical pulses, for 4g range, are shown in Figure 4.
Figure 4:
Pulse-train range signal for +/-4 g range.
AUTOZERO
The EpiSensor2 has an autozero capability that will remove DC-offsets from the signal, up to an
acceleration-equivalent limit of +/-100 mg. Autozero operates simultaneously on all three channels.
There are only two modes: ON and OFF. The current state is stored in non-volatile memory. The sensor
will enter the appropriate state after a POR event.
There are three ways to control the autozero state:
Button Pushing
1.
Press the button once for about 1 second (0.2 to 2 second acceptable window). This will light
the LEDs and “enable” the system
2.
Push and hold the button for between 5 and 10 seconds to toggle the AUTOZERO ON/OFF. A
green LED will be lit when AUTOZERO is ON
3.
After 20 seconds of inactivity, the LEDs will shut off and the system will be disabled
Q330 Enable Lines (Q330 used for this description)
1.
The sensor monitors Q330 Generic Enable line 1.
2.
A pulse-length encoding scheme is used to set the AUTOZERO state:
⋅
Asserting the line for between 1 and 3 seconds (2 seconds nominal) turns AUTOZERO ON
⋅
Asserting the line for between 4 and 6 seconds (5 seconds nominal) turns AUTOZERO OFF
RS-232 Command Line Interface
1.
At the MAIN prompt, enter “enable12345” to allow access to command menus
2.
Type “OPERATE” to select OPERATE page
3.
At the OPERATE prompt, type command to select range:
⋅
“AUTOZEROON” turns ON Autozero
⋅
“AUTOZEROOFF” turns OFF Autozero
Page 10
August 2015