6-10
power on the Base Station and have the Terminal Sign On again in order to
continue.
Sequence Error Message
The host program must observe the one-for-one "host prompt/terminal
response" protocol at all times. The host cannot send a second data entry
prompt until it has received a response to the first data entry prompt. If it
does, this is considered a
Sequence Error
. If the Base Station receives a
command that is out of sequence, it sends the following message back to the
host:
Byte position
Function
Possible values
1
RF Terminal ID
0-9, A-Z, a-z, - =
2+
Sequence Error
DC2 (ASCII 18)
Last
Termination of message
CR (ASCII 13)
If the Base Station receives 5
Sequence Error
’s in a row, it transmits the
following message to the Terminal and shuts down: (the only host
command that it will receive is *@EOT)
Base Shut Down
Due to Host Logic
Error
Check your program for the sequence error before starting again. You will
have to reinitialize the Base Station by host program control (*@EOT) or
manually cycle power on the Base Station and have the Terminal Sign On
again in order to continue.
Illegal Command
•
When a terminal receives an illegal statement from the host, it will display
the entire statement on the terminal. Once the ENTER key is pressed on
the terminal, the terminal sends a “?” back to the Base Station.
Byte position Function
Possible values
1
RF Terminal ID
0-9, A-Z, a-z, - =
2+
Illegal Command
?
Last
Termination of message
CR (ASCII 13)
For example, if Terminal #2 received an illegal command, the Base
station would transmit to the host:
2?CR
•
If a command is sent from the host to the base station without a
valid terminal ID character, such as:
@1,1,1,Scan Serial Number
