3.4 LED STATUS INDICATOR
The Model 3022 has one LED indicator, which is located at the rear
of the unit, between the two modular jacks (see Figure 2, below). This
LED glows to show that the local and remote Model 3022s are in Data
Mode, and are synchronized with each other.
3.5 POWER REQUIREMENTS
The Model 3022 derives all necessary operating power from the
DB-25 interface, and requires no AC power or batteries for operation.
When the DCE device is turned on, the Model 3022 automatically
“powers up”. Note: If you do not use a modem (as in Section 3.3), or
your modem is interface powered, you will need to obtain a Patton
Model 3P-MF power supply adapter. This adapter plugs into a standard
AC wall outlet and supplies 100 milliwatts to pins 7 and 9 of the DB-25
interface.
3.6 FLOW CONTROL REQUIREMENTS
For each of the Model 3022 port connections, flow control may be
set for X-ON/X-OFF (software), RTS/CTS (hardware), both methods or
no flow control (see Figure 3, below). For
most applications, the serial
devices connected to sub-channels 1 and 2 must support local flow
control (flow control between the device and the sub-channel port). In
all cases, the flow control setting of each Model 3022 port must match
the flow control setting of the device connected to that port.
4.0 OPERATING MODES
This section gives descriptions of the five operating modes used by
the Model 3022. When reading these descriptions it may be helpful to
refer to the Navigation Chart shown in Figure 4 (below).
7
8
Figure 2. Model 3022 rear view showing LED indicator
LED Indicator
Port 1
Port 2
Figure 3. Model 3022 flow control requirements.
Device A
Device B
Model
3022
Modem
Local Flow
Control
Local Flow
Control
Composite Flow
Control
Power Up
Local Offline
Command Mode
Online
Data Mode
Remote Online
Command Mode
Local Online
Command Mode
PassThru
Mode
“\\\”
AT[Y0
(hangup) AT[H
“\\\”
AT[O
AT[D1
AT[D0
AT@
(send commands to
remote Model 3022)
Figure 4. Navigation Chart for the Model 3022 Operating Modes
Where y ou see the above arro w y ou ha ve three
methods of going to Online Data Mode: 1) by letting
the kill timer ( AT[Kn) expire; 2) by the local modem
raising CD (AT[Xn, where n=1); 3) by keying AT[O to
go directly into Online Data Mode.