User's Guide Modem 56

Page 240
ATS82 Failsafe Flow Control Overrun
This S Register works in conjunction with the AT&K9 command. If you are in &K9 mode and
the modem needs to assert flow control it first drops CTS. If the host is using CTS flow control
it should stop sending further characters. If the host is using XOFF flow control it will ignore
the CTS signal and keep sending data. S82 determines the number of characters the modem will
accept after dropping CTS before sending XOFF. If the value is too low some hosts will not
respond to the CTS quickly enough. If the number is too large the buffer might overflow.
Examples
ATS82=20 Accept 20 characters after CTS is dropped before sending XOFF
Default
60
See Also
S Register 80 Flow Control High Water Mark
S Register 81 Flow Control Low Water Mark
&K command Flow Control
Range
1-255