Dell 3250, Руководство по эксплуатации продукта

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Inhibiting and restarting is accomplished through an INT 16h mechanism. The standard INT 16h
(keyboard handler) function ah=05h places a keystroke in the key buffer, as if an actual key is
pressed. Keystrokes buffered this way are examined by redirection; if a valid command string has
been sent, it is executed. The following commands are supported:
•
Esc-CDZ0 - Inhibit Console Redirection. In order to inhibit redirection, the software must call
INT 16h, function ah=05h five times to place the five keys in the key buffer. Keystrokes sent
to the INT 16h buffers to invoking a command are buffered, and should be removed through
normal INT 16h calls to prevent these keystrokes from being passed to another application.
When redirection is inhibited, the serial port is released and can be used by other applications.
•
Esc-CDZ1 - Restart Console Redirection. Restarting reclaims the serial port and continues
redirection
Keystroke Mappings
During console redirection, the remote terminal sends keystrokes to the local server. The local
server passes video back over this same link.
For keys that have an ASCII mapping, such as <A> and <Ctrl><A>, the remote sends the ASCII
character. For keys that do not have an ASCII mapping, such as <F1> and <Alt><A>, the remote
sends a string of characters, as defined in Tables 21 and 22. The strings are based on the ANSI
terminal standard. Since the ANSI terminal standard does not define all the keys on the standard
101 key U.S. keyboard, such as <F5> - <F12>, <Page Up>, and <Page Down>, mappings for these
keys are available.
<Alt> key combinations are created by sending the combination ^[} followed by the character to be
<Alt> modified. Once this Alt key combination is sent, the next keystroke sent is translated into its
<Alt>-key mapping. In other words, if it is mapped to <Shift><F1>, then pressing <Shift><F1>
followed by ^[} sends <Alt><a> to the server.
The remote terminal can force a refresh of its video by sending ^[}.
Combinations outside of the ANSI mapping and not in the table below, such as <Ctrl><F1>, are not
supported.
Table 21. Non-ASCII Key Mappings
Key Normal Shift Ctrl Alt
ESC ^[ NS NS NS
F1 ^[OP NS NS NS
F2 ^[OQ NS NS NS
F3 ^[OR NS NS NS
F4 ^[OS NS NS NS
F5 ^[OT NS NS NS
F6 ^[OU NS NS NS
F7 ^[OV NS NS NS
F8 ^[OW NS NS NS
F9 ^[OX NS NS NS
F10 ^[OY NS NS NS