Sensoray 118 - Manual (Page 5)

Sensoray Model 118 Smart A/D™ Instruction Manual 3 Hardware Configuration
2.3 Board Layout
Figure 2: Board Layout
2.4 Reset State
At power-up, or after a soft reset (see Section 5.1) or a
system hard reset, the Smart A/D™ board is in its default
state as follows:
• Standard speed mode (22ms/channel) is selected.
• 60Hz rejection mode is active.
• All channels are enabled for scanning.
• Sensor data values are reset to zero. Sensor data is not
available immediately after a board reset. The
maximum elapsed time that must pass before new
sensor data becomes available is equal to 35 channel
slot times. Details of channel slot timing can be found
in Section 8.1
• Channels are configured for the 5-volt input range,
with 500µV resolution.
• Software filter constants are set to zero (disabled).
• Alarm threshold limit values are indeterminate.
• All channel alarms are disabled.
• All channels are programmed to fail high upon
open-sensor detection.
2.5 Fault Indicator
A red light-emitting diode (LED), located near the edge
of the Smart A/D™ board, is used as a status indicator.
This LED is energized under either of the following
circumstances:
• A board reset is in progress.
• A board fault has been detected.
When the Smart A/D™ board is functioning normally,
the LED is energized for approximately one-half second
in response to a board reset, either hard or soft. In the
case of power-up and hard resets, this time period may be
extended as the result of a stretched hardware reset signal
on the system bus.
If the LED is persistently energized, there may be a
hardware fault on the A/D board. In this case, be sure to
check all sensor connections, board orientation and
seating, etc. before concluding that the board has a fault.
SCC Enable
Option Shunts
Base Address
Selection
Switches
P1 Header
Fault
Indicator