Black Box 5000 - Manual (Page 126)

Multiserver 5000
124
10.9 Connect Protocol Details
Connect protocol is option 1 of the Switching
Parameters menu. There are three connect
protocol options: Dedicated, Auto, and DTR. A
discussion of the protocols and how to configure
them is in Section 10.7, Asychronous Channel
Switching Parameters
, and Table 10-2. This section
discusses how the call request, completion, and
disconnect sequences operate for the dedicated,
auto-answer, and DTR protocols.
Definitions :
Calling port: Receive Inhibit = on
Call Inhibit = off
Receiving port: Receive Inhibit = off
Call Inhibit = on
Dual port: Receive Inhibit = off
Call Inhibit = off
NOTE: The Dual port is both a calling and receiving
port.
D EDICATED P ROTOCOL
Call Request (Calling and Dual port)
Idle State: Multiserver holds DSR, CTS, and
CD high. RI is held low.
• Data activity automatically triggers a call
request.
or
• If ABR (auto baud rate) is enabled, type
<cr>
to trigger a call request (see
Section 9.3, Asychronous Channels ).
Call Completion (Receiving and Dual ports)
No indication of call completion unless
the called port is an ABR port. Then the
port is set to the calling port’s speed, and
the sign-on character is forwarded.
Disconnect Sequence (Calling, Receiving, and Dual
ports
Calling port:
1. Device initiates
<break><break><break> .
2. Multiserver sends DISCONNECTED
message.
Receiving port
1. Device initiates
<break><break><break> .
2. No indication of disconnection.
DTR P ROTOCOL
Call Request (Calling and Dual ports)
Idle State: DTR can be high or low.
Multiserver holds DSR, CTS, CD,
and RI low.
1. Device raises or toggles DTR.
2. Multiserver then raises DSR, CTS, and
CD.
3. If ABR is enabled, <cr> should now be
typed (see Section 9.3, Asychronous
Channels
).
Call Completion
For Receiving port
Idle State: DTR must be high, otherwise the
port is put out of service (OOS). In
either case, the Multiserver holds
DSR, CTS, CD, and RI low.
1. Multiserver raises DSR, CTS, and CD.
2. No response is required from the device.
3. If ABR is enabled, then <cr> will be
forwarded.