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4.2.6 KB & KBIF PCB description
4.2.6.1 KB
Provides appropriate keystroke, key click and illumination by backlight LED as an
control panel of rubber sheet.
(1)
LED
Two types of red and green LED. Turned ON/OFF according to the key status.
(2)
Key switch
Depressing the key switch outputs ON and releasing it outputs OFF signal.
(3)
Toggle switch
Pressing upward or downward the toggle switch outputs ON signal and returning to
the center outputs OFF signal.
(4)
Rotary encoder
Depressing the rotary encoder outputs ON signal and releasing it outputs OFF signal.
Turning the rotary encoder clockwise outputs positive value and counterclockwise
negative value.
(5)
Slide variable resistor
Variation of resistance outputs variation of data value.
4.2.6.2 KBIF PCB
Controls overall keyboard unit for communication with the main unit (RS232C, PC/2
keyboard, PS/2 mouse) and processes corresponding to each command.
(1)
Key scan
Depressing the key obtains a key scan data from the scan line output.
(2)
Rotary switch and rotary encoder scan
Depressing the rotary switch detects signals and recognizes the rotary switch selected
to make it ON. Releasing it makes it OFF.
Setting data to any specific address selects a rotary encoder to obtain data from the
specific address.
(3)
Slide variable resistor scan
Periodically obtains data of the slide variable resistor converted by the A/D converter
built in CPU.
(4)
Interruption process by each signal
Depressing the FREEZE key obtains data from IRQ6.
SYNC_ERR signal acquires data from IRQ5 based on data sent from the system.
R-wave trigger signal acquires data from IRQ7 based on data sent from the ECG unit.
SPARE0 and 1 signals acquire data from the data bus based on data sent from the
system.
(5)
PS/2 keyboard interface
Acquires a control command for the OADG standard section of the keyboard by
communicating with the system via the PS/2 keyboard interface.
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L1E-EA0229
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