Quartech 9605, Product Manual

Section 2: Operating the 9605

Page 3

PM9605 Revision 1, 9605 Version 36.1.1

2.2  Switch Image bits, Mode B

The switch Image bits, within the Dialogue File, will be used to indicate the status of the 9605's
switches.  The function of the switch image depends on how the switch is configured, i.e. pushbutton or selector
switch.

Configured as Pushbutton Switch -

When a switch is not being pressed, its image bit will be cleared to zero (0) by the 9605.  Its corresponding LED
will be off.  When a switch is pressed, the 9601 will set its image bit to one (1), 
and its corresponding LED will light red.

Push-button truth table

Switch

Image bit

LED

Open

0

Off

Closed

1

Red

Configured as Selector Switch -

The 9605 will control the status of the selector switches using a read-modify-write procedure.  The 9605 will first
read the status of the switch image bits from the SLC-500, then if the switch is pressed, it will compliment the state
of the associated register bit.  For example, if the register bit is energized and the switch is pressed, the register bit
will be de-energized by the 9605. If the register bit is de-energized and the switch is pressed, the register bit will be
energized.  This action produces the push-on/push-off selector switch effect.

The corresponding LED will illuminate green if the Image bit is a zero and red if the bit is a one.

Selector Switch truth table

Switch

Image bit

LED

open

No Change

If image bit = 0 = Green
If image bit = 1 = Red

pressed

If 0 -> 1

Red

If 1 -> 0

Green

2.3  Switch Image bits,  Mode A

The Switch Image bits perform the same function in Mode A as they do for Mode B.  The difference for Mode A is
that the 9605 will not control its LEDs based on the status of the Switch Image Bits.  The LEDs must be controlled
by the SLC-500's application program, using the Green, Amber, and Red LED bits.