GPS Frequency disciplined oscillator.

Generates and corrects 5 MHz signal on CLK1 using GPS PPS time base. User can set CLK0 to anything and it
gets generated incorporating the CLK1 corrections.


Parts:

Etherkit Si5351A Breakout Board with TXCO option
	https://www.etherkit.com/rf-modules/si5351a-breakout-board.html
Adafruit encoder and knob
	https://www.adafruit.com/product/377
Adafruit GPS breakout and antenna
	https://www.adafruit.com/product/746
	https://www.adafruit.com/product/960
	https://www.adafruit.com/product/851
Adafruit 2.8" TFT LCD display with capacitive touch screen
	https://www.adafruit.com/product/2090
Arduino Nano
	https://store.arduino.cc/usa/arduino-nano


Connections:

Nano:

5V	5 V
GND	Common
D2	Encoder B
D3	Encoder A
D4	Encoder S1
D5	EK J8-1
D6	GPS RX
D7	GPS TX
D8	GPS PPS
D9	TFT D/C
D10	TFT CS
D11	TFT MOSI
D13	TFT CLK
A4	TFT SDA  and  EK SDA
A5	TFT SCL  and  EK SCL

Etherkit EK:

5V	5 V
GND	Common
SDA	Nano A4
SCL	Nano A5
J8-1	Nano D5
J8-2	Common
Jumper	J2 5V
Jumper	J3 VREG EXT
CLK0	Output

GPS:

VIN	5 V
GND	Common
PPS	Nano D8
RX	Nano D6
TX	Nano D7

TFT display:

Vin	5 V
GND	Common
D/C	Nano D9
CS	Nano D10
MOSI	Nano D11
CLK	Nano D13
SDA	Nano A4
SCL	Nano A5

Encoder:

A	Nano D3
B	Nano D2
C	Common
S1	Nano D4
S2	Common
