Worth Data RF Terminal 7000 - Manual (Page 49)

a valid command - remember that all messages must end with a request for data input. The host should then
expect a response from the terminal of Terminal ID + DATA (none if only pressing ENTER key) + CR.
SIGN ON is a good way for the terminal operator who has not received instruction from the host for several
minutes to determine if he is still connected and if the host is still functioning. By SIGNing OUT and
SIGNing back ON, the operator should receive a message that there is nothing to do. It is also a good idea
for the host to keep track of elapsed time that a terminal has not had a message sent out to it. The host
should then send a message periodically to re-assure the operator (remember to ask him to press ENTER)
that instruction is coming or tell him to see his supervisor for re-assignment (or whatever makes sense for
your application).
Ideally, if the operator is leaving the area (to go to lunch or move to another building) before he is out of
range of the network, he should SIGN OUT, then SIGN ON upon his return.
A 6 line display terminal configured as a 6 line display (see Installation and Setup for LCD DISPLAY
MODE) sends ASCII 22 as its SIGN ON character. A 6 line display terminal configured as a 4 line display
will transmit the ASCII 15 character for SIGN ON.
SIGN OUT
When a RF Terminal is powered down manually or the user presses the F1 key to exit data entry mode to go
to one of the other modes (SETUP or ONE WAY), the host receives the following SIGN OUT message:
Byte position Function Possible values
1 RF Terminal ID 0-9, A-Z, a-z, - =
2+ SIGN OUT SO (ASCII 14)
Last Termination of message CR (ASCII 13)
Base Station Error Feedback
The following are four different unexpected feedbacks that the Base Station can send back to your program:
(Be sure to look for each of them to be sure your program doesn’t blow up at an unexpected time.)
Addressing a Terminal not SIGNed ON
If the host attempts to send a message to a terminal that is not SIGNed ON, the Base Station sends back the
following message to the host computer:
Byte position
Function Possible values
1 RF Terminal ID 0-9, A-Z, a-z, - =
2+ Terminal NOT Signed In DC1(ASCII 17)
Last Termination of message CR (ASCII 13)
The ASCII 17 character can be changed to ASCII 16 for XON/XOFF sensitive systems by changing the
Base Station Setup. See Chapter 2; RF System Setup for details.
If the Base Station receives five Addressing a Terminal not SIGNed On messages in a row, it transmits the
following message to the Terminal and shuts down: (it will recognize a reinitialize command (*@EOT)
from the host though)
Base Shut Down
Due to Host Logic
Error