Worth Data 701 RF manual Automatic Check Back, Base Station Initialized Message

since the command doesn’t specify which terminal it is meant for, the base sends the following message back to the host:

*?CR

•If the Base Station receives more than 231 characters, it treats that statement as an Illegal Command. If it sees more than 231 characters 5 times in a row, it transmits the following message to the Terminal and shuts down:

Base Shut Down

Due to Host Logic

Error

You can re-initialize the terminal by sending *@EOT or by powering the base off and back on.

Automatic Check Back

When a terminal checks back in to see if there is a change in instructions, the host can send back the same prompt or send back a new prompt. The check back occurs according to the time specified in the Terminal's setup, (specified in increments of 5 seconds). When a check back occurs, the Terminal clears the screen of the current prompt, and sends back the following message:

Byte position	Function
1	RF Terminal ID
2+	Check Back
Last	Termination of message

Possible values

0-9,A-Z,a-z,-=

BEL (ASCII 07)

CR (ASCII 13)

Base Station Initialized Message

Whenever the Base Station is powered up, it sends a message back to the host as follows:

Byte position	Function
1	BASE ID
2+	Base Initialization
Last	Termination of message

Possible values

*(Base ID is fixed) DC3 (ASCII 19) CR (ASCII 13)

Since ASCII 19 is XOFF, the ASCII 19 character can be changed to ASCII

20 for XON/XOFF sensitive systems by changing the Base Station Setup. See Chapter 2; RF System Setup for details.

The Base Station Initialized message is provided so that the host will know that there has been a power interruption on the Base Station. When a serial device powers up, the first byte transmitted is often garbage. QBASIC handles the garbage character without incidence, but GWBASIC does not unless ON ERROR GOTO is used to trap the error. Be aware of this potential garbage-byte problem in your programming. To isolate and

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