Contec AD12-8(PM), Руководство пользователя

Страница: 59 / 81

4. Functions
52
AD12-8(PM)
3. Monitoring the Status and Acquiring Data
Software commands are used to monitor the operation status of the device and to acquire input data
from memory. Status monitoring and data acquisition can be performed even during sampling.
Status
The current state of the device can be checked by obtaining the device status.
The following types of device status are available:
- Device operating
The “device operating” status remains ON, after the execution of the sampling start command until
the PC card completes conversion, aborts operation due to an error, or stops sampling in response to
the command.
- Waiting for start trigger
This status remains ON, after the PC card starts sampling until the start trigger is input, if the
conversion start condition is level comparison. The status is set to OFF when the input trigger is
input to start conversion.
The status is set to ON whenever the PC card enters the conversion start wait status even when
repeated operation has been set.
- Specified sampling data stored
This status is set to ON when input data stored in memory has reached the amount corresponding to
the preset number of times of sampling.
If the memory format is FIFO, the status is set to OFF when the amount of input data in the memory
falls below the value corresponding to the preset number of times of sampling as data is acquired.
Once the status is set to ON when the memory format is ring, it remains ON until it is reset.
- Overflow
An overflow error occurs when an attempt is made to store input data to memory while it has been
full of input data.
When the memory format is FIFO, the PC Card stops conversion.
When the memory format is ring, the PC Card continues conversion while overwriting existing data
with new one.
- Sampling clock error
This error occurs when the sampling clock period is too short.
- AD conversion error
If the “device operating” status remains ON (without terminating conversion) for an extended
period of time, the driver regards that state as an operation error and sets this status to ON. This
error stops sampling.
Sampling
The number of sampled items of input data stored in memory can be obtained by the software
command.
Repeat
The current repeat count can be obtained by the software command.