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3 -------------------------------------------------------------------------------
5 This is a collection of PS/2 keyboard communication examples.
7 A random PS/2 keyboard and a random PC mainboard were used as data source.
10 https://web.archive.org/web/20161231114842/http://www.computer-engineering.org/ps2protocol/
11 https://www.avrfreaks.net/sites/default/files/PS2%20Keyboard.pdf
17 The logic analyzer used was a Saleae Logic (at 24 MHz):
25 ps2_keyboard_asdfgh.sr
26 ----------------------
28 This file contains a sequence of keypresses on a standard PS/2 keyboard:
29 a, s, d, f, g. The dump contains the "make code" and "break code" of each key.
31 After each transmission, the receiving controller appears to pull the clock
32 line low for more than 100 microseconds. This inhibits transmission until the
33 clock line is released, presumably because the receiving controller needs time
34 to process data. Due to this, additional very short clock pulses can be
35 observed, as the controller starts inhibiting communication only shortly after
39 ps2_keyboard_asdfgh_no_inhibit.sr
40 ---------------------------------
42 The keys a, s, d, f and g pressed on a random PS/2 keyboard.
44 In this dump, the receiving end was passive, without inhibiting communication.
45 Thus only clock pulses produced by the keyboard can be observed.