Article
Keyboard/Mouse Switch Unit
Unplugging or re-connecting equipment to the serial COM or PS2 connector always gives problems if the PC is running. Even if you only need to swap a mouse or changeover from a graphics keyboard to a standard keyboard. The chances are that the connected equipment will not communicate with the PC, it will always be necessary to re-boot. If you are really unlucky you may have damaged the PC or the peripheral device.
Materials
Gerber file
CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor GREEN and GOLD members can exclusively download these files for free as part of their membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service.
Elektor recommends the Elektor PCB Service service from its business partner Eurocircuits or AISLER as the best services for its own prototypes and volume production.
The use of our Gerber files is provided under a modified Creative Commons license. Creative Commons offers authors, scientists, educators and other creatives the freedom to handle their copyright in a more free way without losing their ownership.
PCB
Component list
Resistors:
R1 = 2kOhm 2
R2 = 47kOhm
R3 = 10kOhm
R4 = 4kOhm 7
R5 = 1kOhm
R6 = 1kOhm 2
Capacitors:
C1 = 10µ F 10V radial
C2 = 1000µ F 10V radial
C3 = 2200µ F 10V radial
C4 = 2µ F2 10V radial
Semiconductors:
D1-D5 = 1N4148
T1 = BC547
IC1 = 4066 or 74HCT4066
Miscellaneous:
RE1 = bistable relay 4 c/o contacts (Takamisawa, Conrad Electronics #502936)
RE2 = monostable relay 2 c/o contacts (Takamisawa, Conrad Electronics #504700)
K1,K2,K3 = 6-way Mini-DIN socket (pins at 240°, PCB mount
S1,S2 = pushbutton (ITT D6-R)
R1 = 2kOhm 2
R2 = 47kOhm
R3 = 10kOhm
R4 = 4kOhm 7
R5 = 1kOhm
R6 = 1kOhm 2
Capacitors:
C1 = 10µ F 10V radial
C2 = 1000µ F 10V radial
C3 = 2200µ F 10V radial
C4 = 2µ F2 10V radial
Semiconductors:
D1-D5 = 1N4148
T1 = BC547
IC1 = 4066 or 74HCT4066
Miscellaneous:
RE1 = bistable relay 4 c/o contacts (Takamisawa, Conrad Electronics #502936)
RE2 = monostable relay 2 c/o contacts (Takamisawa, Conrad Electronics #504700)
K1,K2,K3 = 6-way Mini-DIN socket (pins at 240°, PCB mount
S1,S2 = pushbutton (ITT D6-R)
Discussion (0 comments)