ADLINK Technology NuDAQ ACL-8454, User Manual

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Registers Format
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31
BASIC language
To write an output port:
10 BASE=&H240
20 VALUE% = &H2F
30 OUT( BASE+2), VALUE %
or
10 OUT( &H242 ), &H20
To read an input port
10 BASE=&H240
20 VALUE=INP( BASE+2)
or
10 VALUE=INP( &H242 )
C language (Borland C++)
To write an output port:
#define BASE 0x240
unsigned int Value=0x2F;
outportb( BASE+2 , Value );
or
outportb( 0x242 , 0x2F );
To read an input port
#define BASE 0x240
unsigned int Value;
Value = inp ortb( BASE+2 );
or
Value = inportb( 0x242 );
Perform Functions
Users should study the operation theorem and the relative data
sheet to understand how to operate this card, then use the low-level
programming to p erform those functions. Generally, the DIO control
can be easily performed by only a few instructions, it is very suitable
to use the low level programming.
As to the higher level functions such as the interrupt service routines,
pulse width measurement, frequency measurement, etc, user may
use the library or modify the examples to carry them out. However,
fully understanding of the PC system is necessary for certain
applications.