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[Cherche] plans commutateur 2 pc -> 1 ecran

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basique, c'est juste galere a faire :

pc1 ---------o

Interrupteur 2positions : 0 ----------Ecran

pc2 ---------o

il faut juste relier les 10000fils de chaque vga a l'interrupteur 2postions qui doit donc avoir 30000fils au total^^essaye pt de recup un switch imprimante sur lequel changer les prises ?

ou alors achete cest vraiment plus simple^^

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Merci bien mais je ne suis pas sur qu'en switch directement les fils ça soit l'idéale.

J'ai trouvé ça sur le net, mais si un electronicien pouvait me le déchiffrer (enfin, en faire un schéma quoi:transpi: ) et surtout me le confirmer merci ;)

Monitor signal switching

Most KVM products are targeted to be used with computers that have VGA connectors. The idea in VGA signal switching is that the signal siwtching matrix routes the RGBHV signals from one PC input to the monitor output. This switching of the signal can be implemented with mecahnical switched, relays or using electronic components (analogue switches, controllable amplifiers etc.).

Here is the pinout of VGA connector:

Pin New VESA DDC    Old VGA

1  Red                      Red

2  Green                  Green

3  Blue                    Blue

4  No Connect          Reserved

5  Ground                Ground

6  Ground                Red Ground

7  Ground                Green Ground

8  Ground                Blue Ground

9  No Connect          No connect

10  Ground                Ground for syncs

11  No Connect          Monitor ID 0 (ground)

12  DDC DAT            Monitor ID 1 (no connect)

13  Horizonal Sync      Horizonal Sync

14  Vertical Sync        Vertical Sync

15  DDC Clock          No Connet

For monitor switching you need to switch at least pins 1,2,3, 13 and 14 to make the monitor signal switch nicely. You can generally leave the ground pins (6,7,8, 10) connected all the time. With a modern plug&play monitor it is a good idea to connect also pins 12 and 15 so that the monitor-computer DDC communications works well (this is used by plug&play / plug&display features).

A typical mechanical switch works around this way: Mechanical changeover switches/relays to select between two input signal sources. For VGA connection geneally pins 1,2,3,6,7,8,13,14, and 10 of the monitor connector are switched (usually also 12 and 15 so that DCC for plyg&play monitor connection works). There are some variations what pins are switched (some implementations do not switch the ground lines, they keep then always connected. some other switch also those lines).

A mechanical switch will work for VGA signals quite acceptably when the internal wiring on the switch box is well made (preferably 75 ohm coax).

Electronic switches comprise a video switch that switches analog video and sync pulses between shared monitors and computers. Many modern VGA switching system use electronic switching of VGA signals.

Keyboard switching

Simplest keyboard siwtches can use mechanical changeover switches/relays to select between two PCs which one is wired to the keyboard connector. Using mechanical switch is almost like unplugging keyboard from one computer and hooking it up to another. Usually this wont cause serious problems but sometimes it can cause strange problems (erratic keyboard operation, noise characters to PC, even system crash with some computers). So mechanical switch is an inexpensive solution what works if the demands are not very high.

Electronics can be used to make things work more smoothly. Modern electronics KVM switch has a microcontroller that is all the time connected to two PCs plus the keyboard. This microcontroller emulated the real keyboard operation to the PCs (so the PCs think that they are connected real keyboard) and at the same time communicated with the real keyboard (received information on keys pressed and sends them to PC that should receive them at this time). In this way you can switch the keyboard control between tho PCs smoothly without any problems.

Mouse switching

A modern PS/2 type mouse uses similar connector and quite similar signals as a keyboard. The siwtchign of mouse signals is typically implemented quite much in the same way as the keyboard switching.

There are also some new switches that have USB switching in them.

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