Setting the handshake line parameters – Agilent Technologies L4400 User Manual
Page 216
204
L4400 User’s Guide
8
L4450A 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)
N O T E
The settings for drive mode, output drive level, and input threshold also
apply to the bank’s interrupt line.
N O T E
When using external pull-ups in the open collector mode, the outputs
will not exceed 5 V.