Expanded Remote Control Outputs - ACC RC-85 Owner's Manual

RC-85 Repeater Controller Owner's Manual
The remote control outputs are controlled by User level commands and may be
forced on or off, and may be interrogated. When any output is interrogated, a
short (100us) pulse is generated on that output - that is, the output toggles to
the opposite state and back. The pulse is too short to disturb equipment being
controlled, but long enough to trigger a one-shot or 555 timer to stretch to any
duration required.
One of the control outputs may become the Link PTT when a link or remote base
transceiver is installed. Its function is DIP switch selectable.
The other logic outputs may have dedicated functions when certain options are
selected. If commanded to the "Phone Line Shared" mode with a Configuration
command, Control Output 3 (UF3) becomes an active low Phone Line In-Use
output, which may be or-tied with other controllers at the site to indicate that
another controller is currently using the phone line. See "Sharing the Phone
Line" later in this chapter.
An external cartridge tape player may be interfaced to the controller and play
ID, tail or Bulletin Board messages. The activation of these messages when
loaded properly with the Message Editor may cause a one second pulse to be
generated at Control Output 2 (UF2) to start the external device. The controller
then monitors the External Device Busy logic input for indication of completion
of the recorded message. See "External Tape Player" later in this chapter for
details.

Expanded Remote Control Outputs

Two alternative modes (DIP switch selectable) use two or three of the outputs to
serially shift out eight remote control logic functions plus remote base frequency
information (see next section) - a total of 24 bits. The eight remote control
output functions permit more extensive remote control of equipment at the site
at the expense of several external IC's required to capture the data. The FC-1
Frequency Control Board is available from ACC for this purpose.
One expanded mode shifts the serial data out of two control outputs which
function as a serial clock and serial data line. External shift registers capture
the data and provide it to the system in a parallel format. Since the output data
is disturbed as the new data is shifted into the registers, glitches appear on the
recovered outputs, which is acceptable in many applications but not in others.
Another mode is supported which adds a transfer pulse, which can load the new
data into parallel registers after it's shifted, without glitches appearing on the
recovered outputs. The FC-1 board, which uses 4094B shift / store registers, can
recover the data in this mode.
(Interfacing to Other Equipment) 8 - 5 V3 4/87