Arduino nixie v41, Руководство по эксплуатации

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“TICK LED” Circuit:
Parts List:
RTC RTC (see note)
SV4 CONN_RTC (see note)
R19 1k
R23 1k
Q6 2N7000
TICK LED LED 5mm
SV6 CONN_LED
SV2 CONN_FRONT
R11 10k
This step will check that the Micro-controller can talk to the RTC module, and that the time counting is
working properly. The flashing rhythm of the “tick” LED comes from the RTC module, and we want to check
that we are able to communicate with the RTC module..
Notes:
•
If you want to have two LEDs for the “tick” circuit, you can place these in series, and power them
from the unregulated VIN voltage.
•
Q6 should be orientated with the flat side as shown on the board. Some FETs come with the leads
in a row rather than in a triangle. If this is the case, bend the middle lead slightly so that it fits the
holes in the board (see hint).
•
The RTC module has two sets of contacts on it. You can use either the side with the pins on it or
wire up the other side with flying wires. If you use the side with pins, you should carefully remove
the two unused pins (see hint). If you use the contacts on the module, you should leave CONN_RTC
off the board.
•
If you receive the connector header as a single strip, break off 4 pins for SV6 and 4 pins for SV2.
•
The LED must go with the right polarity. The “-” side has a flat on it, and has the shorter lead (see
hint), and must be connected to pin 4 of SV6.
•
R11 is needed to bias the LDR ambient light detection circuit, to make sure that the LED lights up
reliably.
The LED should be wired up with the longer lead to pin 4 of the CONN_FRONT (SV2) connector and the
shorter lead to pin 4 of the CONN_LED (SV6) connector. (Pin 1 has a little “o” beside it on each connector on
the board).
Test Step
Once you have populated the components, power on. The LED on the RTC module should
come on, and the “TICK” LED should flash on and off slowly (on for one second, off for
one second). It might take a second or two to come on, but after that should “pulse” on
and off.