Bedienungsanleitung AEA PK-232 MBX - Pakratt 232 (Seite 70 von 266) (Englisch)

636052

Zoom out

Zoom in

Vorherige Seite

1/266

Nächste Seite

PK-232 OPERATING MANUAL PACKET RADIO

3. WAlABC>WB2XYZ [C, P] 01 3E 38 58 32 {Packet Lite attempt}

…

In this case, the non-Lite station notices the non-standard bytes

following the control byte but sends no response at all. If this occurs,

you must turn the command LITE OFF and try to connect again to the distant

station. No adverse effects are caused by this, but transparency with

standard AX.25 is lost when the receiving station does not acknowledge a

Packet Lite connect request in some manner.

We know that TCP/IP, NET-ROM and DRSI stations ignore Packet Lite Connect

requests. These stations are normally found on VHF, but to be safe, the

LITE command should be turned OFF when not in use.

4.10.3 Packet Lite Protocol Enhancement Summary

The following describes the Packet Lite protocol extension in detail for

those interested in the technical details. It is not necessary to read or

understand the following section to use the protocol.

Here is a summary of a Packet Lite exchange, where WALABC calls WB2XYZ:

Connect:

W B 2 X Y Z -0 W A I A B C -0 SABM 01 3E 38 58 32

destination  source  CTRL PID  short address

The destination and the source are both 7 bytes long. Everything up to

the CTRL byte (SABM) is standard AX.25 version 2.0. The 'Protocol ID" of

01 hex is Packet Lite's reserved value, which provides a way of

interpreting the following bytes. This leaves room for other extensions

to AX.25 in the future. The short address bytes are the right-justified

bytes of the address field that WAIABC proposes to use in subsequent

Packet Lite frames with WB2XYZ. In this case, the AEA implementation of

the short address is illustrated. 3E38 is a compressed version of the

destination WB2XYZ and 5832 is a compression of WAIABC. However, any

combination of 26 bits may be used (see "Technical Details" below).

Connect acknowledgment:

W A I A B C -0 W B 2 X Y Z -0 UA 01 58 32 3E 36

destination  source  CTRL PID  short address

WB2XYZ replies to WALABC. Again, everything up to the CTRL byte (UA) is

standard AX.25. The 'PID' of 01 and the short address confirm that WB2XYZ

has accepted the Packet Lite connection. The short address is again the

right-justified representation of the address field that WB2XYZ will be

using in subsequent Packet Lite transmissions. In this case WB2XYZ has

accepted the short address field suggested by WALABC, and has shown his

acceptance by echoing the address back in reverse order (5832 = WALABC and

3E38 = WB2XYZ). AEA products always accept the short address from the

SABM frame; however, the Packet Lite protocol allows the sender of the UA

frame to propose a different combination of 26 bits, to avoid conflicting

with another Lite QSO. In either case, the sender of the original SABM

must accept the 26 bits in the UA frame, reversing the address order for

its own transmission

2/93 4-29

Missbrauch melden von Frage und/oder Antwort

Libble nimmt den Missbrauch seiner Dienste sehr ernst. Wir setzen uns dafür ein, derartige Missbrauchsfälle gemäß den Gesetzen Ihres Heimatlandes zu behandeln. Wenn Sie eine Meldung übermitteln, überprüfen wir Ihre Informationen und ergreifen entsprechende Maßnahmen. Wir melden uns nur dann wieder bei Ihnen, wenn wir weitere Einzelheiten wissen müssen oder weitere Informationen für Sie haben.

AEA PK-232 MBX - Pakratt 232 Seite 70

Brauchen Sie Hilfe? Stellen Sie Ihre Frage.

Missbrauch melden von Frage und/oder Antwort

Art des Missbrauchs:

Forenregeln

Neu registrieren

Andere Handbücher von AEA PK-232 MBX - Pakratt 232

Das Handbuch wird per E-Mail gesendet. Überprüfen Sie ihre E-Mail.

Ihre Frage wurde zu diesem Forum hinzugefügt

Info