ADLINK ACL-8216 - Manual (Page 41)

Operation Theorem • 33
4
Operation Theorem
The operation theorem of the functions on ACL-8216 card is described in this
chapter. These functions include the A/D conversion, D/A conversion, digital
I/O and counter / timer. The operation theorem can help you to understand
how to manipulate or to program the ACL-8216.
4.1 A/D Conversion
Before programming the ACL-8216 to perform the A/D conversion, you
should understand the following issues:
• A/D conversion procedure
• A/D trigger mode
• A/D data transfer mode
• Signal
connection
4.1.1 A/D Conversion Procedure
The A/D conversion is started by a trigger source, then the A/D converter will
start to convert the signal to a digital value. The ACL-8216 provides three
trigger modes, see section 5.1.2.
While A/D conversion, the DRDY bit in Status Control register is cleared to
indicate that the data is not ready. After conversion being completed, the
DRDY bit will return to low(0) level. It means users can read the converted
data from the A/D data registers. Please refer section 4.2 for the A/D data
format.