Agilent Technologies L4400 - Manual (Page 226)

214 L4400 User’s Guide
8 L4450A 64-Bit Digital I/O with Memory and Counter
The SOURce:DIGital:INTerrupt:MODE command sets how the bank will
behave when using memory output. The mode can be set to one of three
values:
• STARt : The memory output will begin on the rising edge of the
interrupt line.
• STOP : The memory output is halted on the rising edge of the

interrupt line.
• GATE : The interrupt line acts a a gate for the memory output. The bank
can output when the interrupt line is asserted, and will stop when the
interrupt line is de- asserted.
When you have set the polarity and mode, enable the interrupt using the
SOURce:DIGital:INTerrupt:ENABle command.
Memory Input Operations
For memory input operations, the interrupt line is an output and is set on
a pattern match or when the memory has been filled. You can set the
interrupt line to be driven or open collector using the
SENSe:DIGital:HANDshake:DRIVe command.
The settings for drive mode, output drive level, and input threshold also
apply to the bank’s handshake lines.

When set to ACTive the interrupt line will be driven by the instrument.
The high output voltage is set for both the handshaking and interrupt line
on a bank with the
SOURce:DIGital:HANDshake:LEVel command.
When set to OCOLlector the interrupt line will be driven low, but will go
to high impedance mode when in the ‘High’ state. The open collector mode
requires external pull- ups.
The SENSe:DIGital:INTerrupt:MODE command sets the condition that will
cause the interrupt to be asserted. When set to MFULl the interrupt is
given when the memory is full. When set to COMPare the interrupt is
asserted when the pattern is detected (see page page 216 ). When either
condition is removed, the interrupt is de- asserted.
The interrupt line is enabled by the SENSe:DIGital:INTerrupt:ENABle
command and the status can be checked using the SCPI Status System
(refer to the Programmer's Reference Help file on the L4400 Product
Reference CD- ROM).
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