Table of Contents
Advertisement
Chapter 5, FRONT PANEL OPERATION
5.3.33 Digital Port Menu
When Main Menu 2 is displayed, pressing a key adjacent to the Digital Port menu
item accesses the Digital Port menu, shown in figure 5-41.
Figure 5-41, Digital Port Menu
The Digital Port menu allows the operating mode of each of the eight pins of the
DIGITAL I/O connector on the rear panel of the main console to be set and its logic
status to be set and read. This port may be used for controlling or reading the status
of external equipment, for example the switching of heaters or attenuators, via a
suitable user-supplied external interface circuit.
Each of the eight pins is configured as an input or output by the Bit direction digits;
when the digit is a 1, the corresponding bit is an input; when it is 0 it is an output.
For those bits configured as outputs, the Output value digits define whether they are
high (value = 1) or low (value = 0)
To change a given bit, use the
,
,
and
to move the underscore (_) cursor
until it is under the digit to be changed. Set the required status, either 1 or 0, by using
the numeric keys.
DECIMAL OUTPUT
This control offers an alternative way of changing the output value. The number is
the decimal equivalent of the displayed output value bit pattern, and consequently
can be set to any number between 0 (all bits at logic "0") and 255 (all bits at logic
"1").
DECIMAL INPUT
This displays the current logic state of all eight bits, regardless of whether they are
inputs or outputs. The number shown is the decimal equivalent of the 8-bit value,
and consequently can range between 0 (all bits at logic "0") and 255 (all bits at logic
"1").
Pressing the Previous Menu key returns control to Main Menu 2.
5-55
Advertisement
Table of Contents
