National Instruments AT-MIO-64F-5, User Manual

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Chapter 6 Calibration Procedures
© National Instruments Corporation 6-3 AT-MIO-64F-5 User Manual
The EEPROM is a 128-bit by 8-bit storage area that contains a permanent storage area and a
modifiable storage area. The permanent storage area consists of locations 96 through 127.
While at the factory, these locations can be accessed for a read or a write operation, but in the
field, these locations can only be read from. These locations cannot and should not be written to.
This allows for a permanent set of calibration values that cannot be erased. The modifiable area
consists of locations 0 through 95. These locations can always be read from and written to.
Included in this area are the load area, user areas, and user reference areas. Notice that the load
area contains constants that are loaded at initialization by the software to place the board in a
known and calibrated state.
0 1 2 7 3 4 5 6
Revision Subrevision
MSB LSB
1111 = 15
1110 = 14
0010 = 2
0001 = 1
0000 = 0
. .
. .
. .
1111 = P
1110 = O
0010 = C
0001 = B
0000 = A
. .
. .
. .
Figure 6-2. Revision and Subrevision Field
If the Revision and Subrevision Field contain the binary value 00100010, this signifies that the
accessed AT-MIO-64F-5 board is at Revision C and Subrevision 2. This number can be very
useful in tracking boards in the field and in answering questions concerning board operation.
Board operation sometimes varies depending on the revision or subrevision of the board.
0 1 2
7
3 4 5 6
Reserved
CONFIGMEM Length
LSB MSB
0110 = 16,384
0010 = 1,024
0001 = 512
0000 = 256
0101 = 8,192
0100 = 4,096
0011 = 2,048
Figure 6-3. Configuration Memory Depth Field
If the Configuration Memory Depth Field contains the binary value XXXX0001 where X
indicates don't care bits, this signifies that the accessed AT-MIO-64F-5 board contains a
configuration memory with a depth of 512. Thus, the configuration memory can hold up to 512
configuration values for channel, gain, mode, and range settings.