KFLOP Does Analog Too
With a little help from its friends, flying a bit higher
over Photo 2 reveals a larger I/O interface board
underneath the KFLOP. The larger board that is carrying
the KFLOP in Photo 3 is called Kanalog. The Kanalog
attaches to the KFLOP using the high speed LVTTL
differential communications portal JP5 and general-purpose I/O portal JP7. It may seem that we have lost
some KFLOP I/O pins to the Kanalog. However, Kanalog
is actually an I/O pin force multiplier.
Let’s take a walk around the Kanalog,
beginning with the optoisolator I/O
interface you see in Photo 4.
Kanalog provides eight opto inputs
and eight opto outputs. There is
nothing special about the opto
configurations. Kanalog uses
optoisolators in the standard manner.
The opto inputs are no more than
LEDs with a 10K series resistor. The
opto inputs can be driven with
voltages that range from + 5 to
+ 24 volts.
Note the opto inputs are pinned
out as eight pairs of plus/minus inputs.
The opto outputs are also pinned as
eight pairs of plus/minus outputs. The
JP13 and JP15 opto plus/minus
arrangements pin out the LED anodes
and cathodes, respectively. NPN
transistors make up the opto outputs
with the plus pins attaching to open
collectors, and the minus pins
connecting each respective optoisolator transistor emitter.
Each opto output is rated to handle up to 80 volts at
JP12 is a standard 40-pin IDC header that houses
eight bits of 3. 3 volt LVTTL input and eight bits of 3. 3 volt
LVTTL output. There are also four 0.0-3.0 volt analog-to-digital converter (ADC) inputs among the 40 pins. The
Kanalog has an onboard ± 15 volt 70 mA DC-DC
■ Photo 3.Kanalog combines the compute power of the
KFLOP with optoisolated inputs and outputs, differential
encoder inputs, analog-to-digital inputs, FET relay
drivers, and digital-to-analog outputs.
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■ Photo 4. Note the ribbon cable interface to the Kanalog mounted in JP7.
Kanalog provides eight opto inputs and eight opto outputs.
You can also see the DAC outputs in this shot.
■ Screenshot 8. This is what the user/programmer
sees when the C program clears KFLOP I/O bit 16.