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Tibbo Project System (TPS)
© Tibbo Technology Inc.
LEDs
Each TPP board carries 8 LEDs.
Two status LEDs
These are our standard green and red status LEDs. See
. on how this
LED works.
One Ethernet status LED
The TPP2 has a single Ethernet status LEDs -- the yellow "link" LED. See
. on how this LED works.
Five signal strength LEDs
Five blue LEDs form an LED bar. They are intended primarily for the indication of the
RF signal strength (i.e. of the Wi-Fi signal). These LEDs are controlled through three
GPIO lines 46, 47, and 48.
GPIO46 is the reset line of the LED bar. Clearing this line sets all five outputs LOW
and this turns all LEDs ON. GPIO47 is a clock line- a positive (LOW-to-HIGH)
transition on this line "shifts in" the data on the data line. The LED control circuit is
shown below.