1 ;;; vt100-led.el --- functions for LED control on VT-100 terminals & clones.
3 ;; Copyright (C) 1988 Free Software Foundation, Inc.
5 ;; Author: Howard Gayle
9 ;; This file is part of SXEmacs.
11 ;; SXEmacs is free software: you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation, either version 3 of the License, or
14 ;; (at your option) any later version.
16 ;; SXEmacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with this program. If not, see <http://www.gnu.org/licenses/>.
26 (defvar led-state (make-vector 5 nil)
27 "The internal state of the LEDs. Choices are nil, t, `flash.
28 Element 0 is not used.")
32 (aset led-state l 'flash)
35 (defun led-off (&optional l)
36 "Turn off vt100 led number L. With no argument, turn them all off."
39 (aset led-state (prefix-numeric-value l) nil)
40 (fillarray led-state nil))
49 "Update the terminal's LEDs to reflect the internal state."
50 (let ((f "\e[?0") ; String to flash.
51 (o "\e[0") ; String for steady on.
52 (l 1)) ; Current LED number.
54 (let ((s (aref led-state l)))
57 (setq f (concat f ";" (int-to-string l))))
59 (setq o (concat o ";" (int-to-string l))))))
61 (setq o (concat o "q" f "t"))
62 (send-string-to-terminal o)))
66 ;;; vt100-led.el ends here