Black Box MD1276A, User Manual

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ATS80 Flow Control High Water Mark
This S Register controls when your modem uses flow control to stop data from your computer.
Data to be sent by your modem is stored in a
‘ buffer ’ (a temporary storage area) until it can be
sent by your modem. If the buffer begins to fill, your modem will use flow control to stop your
computer sending more data.
S Register 80 allows you to set the level at which the modem will use flow control stop your
computer sending more data. Unless you have a sound reason for doing so, the high water mark
should never be set higher than 75%. Using a higher water mark may cause problems with
computers that are slow to respond to your modem
’ s flow control.
Each unit is equivalent to 5% of your modem
’ s buffer.
+ Do not change the value of this S Register unless you are an experienced
communications user. An inappropriate value may cause flow control between
your computer and modem to become unreliable.
Refer to the chapter titled
‘ Getting Started ’ for details of flow control.
Examples
ATS80=12 Use flow control when the buffer becomes 60% full
Default
15 (75% of the buffer)
See Also
S Register 81 Flow Control Low Water Mark
&K command Flow Control
Range
1-19