Advanced Instruments 4250, User Manual

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8. Dis/Enable Xon/Xoff
This menu item enables or disables the Xon/Xoff “ handshaking ” proto-
col for RS-232 communication (CTRL-”S” = STOP/ CTRL-”G” = GO).
1. At “ Dis/Enable Xon/Xoff ” , press START to display “ [on] <
Xon/Xof * [off] ” . The current setting is indicated by the symbol,
“ * ".
2. At “ [on] < Xon/Xof * [off] ” , press < or > to enable or disable ser-
ial-port Xon/Xoff handshaking.
3. Press ENTER to store the new setting (or STOP to restore the
original setting).
9. Serial Number
At “ Serial Number ” , press START to display the instrument serial
number ( “ Serial #: 123 ” ). Press STOP to return to the setup menu. This
number is set by the factory and cannot be changed by the operator.
10. Select Plateau Mode
This menu item enables changing the way the 4250 evaluates the
plateau. An idealized, dimensionless freezing point plateau is illustrated
and described in Figure 1.
1. At “ Select Plateau Mode ”, press START to display the current
mode.
2. Press < or > to toggle between plateau-seeking and timed-plateau
detection modes.
3. Press ENTER to store the new setting (or STOP to restore the
original setting).
11. Set % DFB
This menu item enables storing a “ base ” freezing point in the instrument
memory and displaying, with each sample test result, the percent differ-
ence between the test result and the stored base.
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Cryoscope Model 4250 User’s Guide