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Walk Around the BLOCK Walk Around the BLOCK Diagram - A Glossary
Digital Alert Systems Feb 25,2008

DASDEC Inputs


GPI-General Purpose Input

(back panel center terminal strip) The DASDEC has 2
browser programmed GPI inputs. An external contact closure can trigger an action (see
SETUP-GPIO) which includes forward decoded EAS upon closure, Hold Non-National
EAS alerts until closure, Issue RMT on closure etc. This ability maintains the operational
design of some legacy EAS system configurations.
Monitor Incoming Alerts

(RF connector) The DASDEC includes three internal radio
receivers. External antennas provide reception through the three RF inputs. The internal
receivers can be programmed to select channels in any AM, FM, or NOAA band of
frequencies. Audio levels are also software configurable. A fourth mono audio input can
monitor an external receiver or output from another EAS decoder. Incoming audio or
outgoing alerts can be heard on the front panel or auxiliary speakers.
External Receiver

(back panel terminal strip) The DASDEC can monitor an additional
audio input for EAS information as may be required in some locations. Audio from an
external receiver monitoring a fourth EAS source is connected as an analog mono audio
input.
Analog Program Audio Input

(back panel terminal strip) Analog program audio can be
connected as full balanced stereo. Program audio is muted with a mono alert output during
an alert. There is also an auxiliary alert audio output.

RS-232

(DB-9)

The 9-pin serial port on the back panel provides a communication interface,
(input and output) for a wide variety of character generators. It provides emulation of the
Sage and TFT serial protocols. The serial port also communicates with devices used for
digital signage such as the Beta-Bright LED. Four extra RS232 ports can be added using a
USB/Serial port expansion unit.
Mouse and Keyboard (PS/2)

DASDEC local access is easily obtained with a PS/2
mouse, PS/2, keyboard, and a VGA monitor. Therefore, network connectivity is not
absolutely necessary for the DASDEC to become a functional controller, especially when
communicating with non-network devices such as: Character Generators or Digital Signage,
providing GPIO switching to various other locally, yet externally, connected devices.
Microphone Inputs

(3.5mm Jack) The two microphone inputs can be used to record audio
messages for an alert. Audio .wav files up to two minutes in length can be recorded and
stored with a unique filename. Recorded .wav files can be previewed, erased and re-
recorded until the desired result is obtained.

Network

(RJ-45) The DASDEC provides many network services. The most obvious is the
DASDEC Web server. It is remotely LAN accessible from any computer with a web browser
such as Mozilla-Firefox, Safari, Netscape, Opera, or Internet Explorer. The DASDEC utilizes
Hyper Text Transfer Protocol, (HTTP) the underlying protocol used by the World Wide Web.
HTTPS utilizes HTTP with SSL (Secure Socket Layer), a more secure way of transferring
private data to preserve confidential user information. Secure Shell is also enabled as a
network input.
EAS-NET

EAS-NET is a DAS designed peer-to-peer metadata and data protocol for sending
/receiving EAS event information and associated alert data (like text and audio files) over a
network. EAS-NET allows EAS alerts to be forwarded across a network to file systems on
remote devices, including other DASDECs. EAS-NET supports a variety of transmission
protocols (e.g. SSH, FTP, TCP) customizable to a variety of target platforms.

CAP -

Common Alerting Protocol. CAP is an XML file based alert description for use over
a network. The FCC has made CAP transported EAS reception a requirement in future EAS
packages, pending definition by FEMA. The DASDEC is fully CAP compatible in the existing
EAS compliant chassis. The DASDEC will provide CAP reception and conversion to EAS
alongside its current radio based EAS reception. The DASDEC leads the alerting Industry by
coupling together the new and pre-existing alerting requirements in one self-contained 2-RU
chassis.

SSH

Secure Shell program permits a user to remotely log into a similar SSH computer on a
network. SSH provides strong authentication and secure communications over a potentially
insecure network. When SSH is used, such as with a command line, the entire login session,
including the password is encrypted to eliminate malicious intruders from accessing private
data. When SSH encryption is enabled, the user is also protected from IP spoofing, IP source
routing and DNS spoofing.

EAS CentralCasting

The DASDEC can send alerts over a network from one location to
another DASDEC via EAS NET. EAS Centralcasting relies on this ability to gather local alerts
and send them back to a central broadcast facility. At the broadcast studio, a receiving
DASDEC processes and plays the alert which is then

inserted

into the broadcast stream. The
broadcast is sent back to the remote site.

2nd 10/100 T Network Interface in -> USB

The DASDEC utilizes its RJ-45 network
connection to perform many network services. Additional network expansion is supported
through the USB port to allow access via a second network.
Optional EAS monitoring

The DASDEC has one PCI slot available for expansion.
Present models can house an MPEG card, an AES audio card, or a two-port audio input card
to allow monitoring the audio from two extra external EAS sources. This exceeds most
current monitoring requirements and may be applicable for future EAS/CAP requirements

DASDEC Outputs
GPO-General Purpose Output relays

(
back panel center terminal strip & network
)
The
DASDEC is equipped with two browser programmable GPO relays to activate downstream
peripheral devices. The GPO provides a switching mechanism for external devices during
various stages of an alert condition. Relay operation can also be filtered according to alert
code and FIPS locations. The Net/GPO Expander adds extra programmable, alert filtered
relays for use with extra hardware. Extra relays, tied to specific alert types and alert locations
or to specific station hardware, are

required for handling the complexity of EAS
CentralCasting and for MultiStation operation.
VGA CRT Monitor (VGA)

Direct server access is supported via a VGA CRT monitor,
keyboard, and mouse. Simultaneous local and network login is supported and multiple user
sessions are supported. The VGA monitor can also be configured to simulate a full page CG
and display the text of a processing alert.

CG/NTSC Video Out

(RCA) The DASDEC video line-level output (RCA) provides an
NTSC signal displaying a full screen text message of the data from a current alert. This
simulated CG functionality eliminates the expense of adding an external Character Generator
to view an actively relayed alert. This provides a low cost solution for Cable, LPTV and a data
display for EOCs.
RS-232
(DB-9) See description under Inputs.

USB (USB)
The Universal Serial Bus will support data rates of 12 MBPS and up to 127
peripheral devices such as; the RS-232 expansion unit, an additional Ethernet port, printers,
modems, wireless Ethernet, flash drives, and nearly any other external device which utilizes
a USB port.
Analog Program Audio Out
(back panel terminal strip) The analog balanced stereo
output connector provides program audio pass-through. Program audio pass-through also
operates without power. This audio output is internally switched between incoming program
audio and the EAS alert audio. During an alert, the program audio is muted and a mono alert
output is played on one channel of the dual channel output. The alert audio output becomes
simultaneously present with the NTSC alert CG video output to create a complete
aural/visual alert.
Parallel Port - Printer (25-pin D)
The parallel port provides the ability to support a
variety of printers.
Alert & Monitoring Audio
(3.5mm or terminal block) Audio levels are software
configurable. These four (plus two) sources are configurable for audibly monitored. Audio
from the radio receivers or decoders can be configured to play-out an audio announcement
on the front panel speaker prior to the time the alert is forwarded and before it has been
acknowledged. This audio can also be routed to external main and auxiliary audio outputs.
Network

(
RJ-45
)
A large number of outgoing network services are supported on the
DASDEC. Network alert communications is the main strength of the DASDEC platform.

Email (RJ-45)

One outgoing email server can be configured per DASDEC, and it can send
mail to a designated SMTP email relay service. The relay is a separate email server that can
send alert notification messages and reports out through an Intranet or Internet for individual
or