User`s manual

Using the Agilent E1330B Digital I/O Module 33
Chapter 3
Default and Reset States
At initial power-on and following the *RST command, the Digital I/O
module is set to the following states:
Setting the Polarity
The logical true level of the control (CTL) line, the flag (FLG) line, and the
data lines of each port can be set to either TTL high (> 2.5V) or TTL Low
(< 1.4V) levels. SCPI commands use the
POLarity keyword as:
[SOURce:]DIGital:CONTroln:POLarity <POSitive or NEGative>
to set the control line’s (CTL) polarity on port n.
[SOURce:]DIGital:FLAGn:POLarity <POSitive or NEGative>
to set the flag line’s (FLG) polarity on port n.
[SOURce:]DIGital:DATAn:POLarity <POSitive or NEGative>
to set the data line’s polarity on port n.
Example 10 ASSIGN @Dio TO 70918
20 DIM Pol$ [3]
30 Pol$ = "POS"
40 OUTPUT @Dio; "DIG:DATA1:POL "&Pol$
50 END
This program sets the polarity to positive on port 1 data lines. A TTL high
will be input as a 1, or a bit set to 1 will output a TTL High level.
The
*RST (reset) condition is positive polarity for control (CTL), flag
(FLG), and data lines on all ports.
CTL line: 0 = TTL Low
I/O
line: TRUE = input = TTL High
Data, FLG, and CTL line Polarity: POSitive
Handshake mode: NONE