DECSR—Secure Reset

This control function sets the terminal to its power-up state. DECSR lets applications know the exact state of the terminal before any attempted operations. You can use DECSR to guarantee the terminal state for secure connections. DECSR is similar to RIS, but does not perform a disconnect from the host.

Format

CSI 9/11

Pr 3/n

+ 2/11

p 7/0

Parameters

Pr
is a optional random number from 0 to 16383. If Pr is included, then the terminal sends a confirmation (DECSRC) with this number.

DECSR Actions

• Clears user-defined keys.
• Clears soft character sets.
• Clears the screen and all off-screen page memory.
• Returns the cursor to the upper-left corner of the first page.
• Resets the scrolling margins.
• Resets origin mode (DECOM) to absolute.
• Sets visual character attributes to normal.
• Sets the selective erase (DECSCA) attribute to not selectively erasable.
• Sets all character sets to the defaults (G0, G1, G2, G3, GL, GR).
• Erases macro memory.
• Erases the paste buffer.
• Reinitializes the keyboard state by:
  • Clearing the keyboard input buffer
  • Canceling compose sequences
  • Resetting the keyboard to send its default codes (in NVR)
  • Unlocking the keyboard (resetting KAM)

DECSR replaces all set-up parameters to their saved settings or power-up default values. If you include the optional Pr parameter, then the terminal returns a secure reset report to the host.

Notes on DECSR

• DECSR works in all conformance levels (level 1 or higher).
• DECSR works in display controls mode (CRM) and causes the terminal to exit this mode.
• DECSR does not work in VT52 mode or printer controller mode. The host software must explicitly exit these modes. You can send DECSR to an attached printer if the terminal is in printer controller mode.
• The terminal buffers DECSR like any other incoming data.