Helmholz 700-751-HSM11, Manual, Page: 21 / 99

Helmholz Modem 56k 4.1 21
5.2.6 Software data flow control XON and XOFF
Modem
Send data
XON or XOFF character
Application
(E.g.: PC or
control)
When the input buffer of the modem exceeds a certain fill state, the
modem will insert an XOFF character into the data stream to the ap-
plication. This character will cause the application to send no more
data.
It will depend on the according application software if the RTS/CTS
data flow control is supported.
After the modem has processed the input buffer so far, it will insert a XON charac-
ter into the data stream. This character will cause the application to send data to
the modem again. Analogously, the application can control the data stream from
the modem to the application.
The XON/XOFF method is only available when the transmitted data do not con-
tain the characters XON or XOFF, which usually appear only in actual ASCII texts
(7 bit). When binary data (programs, …) are transmitted, or in the XMODEM
transmission protocol, for example, occasionally appearing XON or XOFF charac-
ters would disturb the operation.
5.2.7 Reset
There are four reset options:
¾
A reset is performed after the power supply has been in-
terrupted for a short time.
¾
After the key RESET on the front panel of the modem is
pressed
¾
After the terminal RESET is connected to the terminal
GND
¾
With the help of the terminal program
After the hardware reset, load the user profile 0
After the hardware reset, load the user profile 1
5.2.8 Dial-up delay
The standard TBR21 applies to all public phone networks in
EU countries (Belgium, Denmark, German, Finland, France,
AT&K4
ATZ0 ATZ
ATZ1