8L4450A 64-Bit Digital I/O with Memory and Counter

The following handshake command sets the synchronous handshaking mode for the channels in bank 1.

CONF:DIG:HAND SYNC, (@1101)

This form of the handshaking command also allows you to optionally set the input threshold, output drive level, and polarity of all the handshake lines. For example, the following command sets bank 2 to use synchronous handshaking, with an input threshold of 2.5 V, an output drive level of 2.5 V, and normal polarity. Other parameters such as the handshake timing are set to default values (refer to the Programmer’s Reference Help file on the L4400 Product Reference CD- ROM for details).

CONF:DIG:HAND SYNC, 2.5, 2.5, NORM, (@1201)

You can set parameters by using a sequence of commands instead of the CONFigure macro command. For example, the following command sequence sets the handshaking mode to synchronous, the output drive to open collector, and the handshake rate to 1 MHz.

CONF:DIG:HAND:MODE SYNC, (@1101)

CONF:DIG:HAND:DRIV OCOL, (@1101)

CONF:DIG:HAND:RATE 1000000, (@1101)

Setting the Handshake Line Parameters

You can set the handshake lines’ input threshold, output drive mode, and output drive voltage. These settings affect all the handshake lines in the bank. Handshake line polarity can be set for each individual handshake line.

For example, you can invert the polarity of the handshake line H1 on bank 2 with the following command.

CONF:DIG:HAND:POL INV, H1, (@1201)

You can set the output drive mode, output voltage, and input threshold for all handshake lines in each bank. For example, the following commands set the drive mode to active, the drive voltage to 4.5 V, and the input threshold to 1.0 V on bank 2.

CONF:DIG:HAND:DRIV ACT, (@1201)

SOUR:DIG:HAND:LEV 4.5, (@1201)

SENS:DIG:HAND:THR 1, (@1202)

NOTE

The settings for drive mode, output drive level, and input threshold also

apply to the bank’s interrupt line.

 

 

 

 

When using external pull-ups in the open collector mode, the outputs will

NOTE

not exceed 5 V.

 

 

 

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L4400 User’s Guide

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Image 214
Agilent Technologies L4400 manual Setting the Handshake Line Parameters, Apply to the bank’s interrupt line