Al_digbitstest – Measurement Computing ADLIB WIN User Manual
Page 67

Chapter 19 Digital Input/Output
18-3
18.3 AL_DigBitsTest
Prototype
C\C++
STATUS
AL_API
AL_DigBitsTest(LHLD
lhld, long lChan, long lTestBits);
Visual Basic for Windows
Function
AL_DigBitsTest(ByVal
lhld As Long, ByVal lChan As Long,
ByVal lTestBits As Long) As Long
LHLD lhld
handle of the LDSD
double lChan
specifies the input port channel number
long lTestBits
specifies the input port bits to test
The AL_DigBitsTest function immediately retrieves input status of a digital input port.
Parameter
Description
lhld
Identifies the instance of the logical device subsystem.
lChan
Specifies the input port channel.
lTestBits
Selects the bits that the function will operate on. All bits set in the lTestBits
will be checked for a true (1) condition.
Note:
Digital IO channels 0 & 1 for all supported hardware are only 8 bit ports. Digital Channels 2 & 3, for all
except a Pci5500 (which don’t have ports 2 & 3), are 16 bit ports. The lChan parameter for all Pci55xx
boards should be set to zero. All four digital ports are hardware programmable as either input or output
ports and can be represented by either DINx or DOTx, but not both. Port direction programming is
determined by the first call to either the AL_DigInput/AL_DigBitsTest functions for an input ports or the
AL_DigOuput function for an output port.
Returns:
On success STATUS is set to one (1) if all of the lTestBits are true and set to zero (0) if any lTestBits are
false, otherwise STATUS contains the negative error code that occurred during the call.
Related Functions:
AL_DigInput
AL_DigOutput
Program References:
Adldio01, Adldio23
Supported Logical Device Subsystems:
Pci5500: DIN0, DIN1, DOT0, DOT1
Pci55xx Series: DIN0, DIN1, DIN2, DIN3, DOT0, DOT1, DOT2, DOT3