SCS PTC-IIex, Manual

Page: 95 / 220

6 Commands
6.95 TNC
Default setting: 0
Parameter: 0 Simple PTC terminal mode.
1 TNC mode with Ctrl-A echo.
2 TNC mode with Ctrl-A echo and *-prompt.
Hostmode terminal programs are developed for pure PR controllers (TNC) with The-
Firmware (TF) as firmware. But some properties of the simple command structure
suggested by the WA8DED are not suitable for a modern multimode controller. Thus TF
uses as prompt only an asterisk * - this is for a system with many submenus (e.g. PTC-
IIex) not very supportive. For example the PTC-IIex displays in the main menu
cmd: .
Switching to a submenu the prompt changes, so that the user has the advantage to know
directly which menu is selected.
Some hostmode programs test exactly if a controller with TF is connected – most of all to
determine if the used controller is already in the hostmode or still in the terminal mode.
For this purpose, as response to the ESC character the asterisk prompt is expected. In the
normal mode the PTC does not send the asterisk prompt, because the ESC character is
responded with its own prompt (e.g.
cmd: ).
Programs like SP or TOP will never switch to the hostmode but simply stop the
initialization phase. Without a workaround this programs could not be used with the
PTC-IIex.
This workaround is represented by the
TNC
command.
Using this command, the PTC-IIex, up to the desired extend, adapts its behaviour to react
similar to the
WA8DED command interpreter. The PTC-IIex reacts similar to a normal
TNC if the
TNC
command is activated. This causes somewhat incompatibility to the own
standard, but the necessary adaptions are tolerable. Description of the parameters:
0. normal PTC terminal mode, PTC-IIex prompt as usual.
1. As long as the PTC is not in the hostmode, the charcter Ctrl-A is always echoed. As it
is unlikely in the terminal mode that a Ctrl-A is sent to the PTC, this is not really a
restriction or incompatibility. (Binary data has to be transfered using hostmode). But
the echo of the Ctrl-A character is necessary when using
WinGT . Unfortunately
without these echo WinGT will idle a minute after startup. But with TNC set to 1
there won´t be a waiting period and the program starts immediately. If TOP or SP are
not used the PTC-IIex can always be operated with the TNC set to 1.
2. The PTC-IIex shows the same behavior as in the TNC 1 mode, but additionally the
prompt will be altered to asterisk *, i.e., the PTC answers to a ESC character not with
the
cmd:-
prompt but with the asterisk. This setting has to be used to operate the PTC-
IIex with TOP or SP as the terminal. Unfortunately sometimes the Asterisk collides
with other terminal programs expecting the
cmd:-
prompt. With
PlusTerm
or
programs similar to this the TNC parameter should be set smaller than 2.
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