software switches for Beacon mode and receive mode (compile time settable)

finish PCB and Schematic Design and baseline for 1.0.

create a #define for having an LCD attached
#define OPTION_LCD true // outputs to an LCD
#define OPTION_LCD false // removes LCD code, no output
allow row and col to be set by #defines.

Desired Features

• add SD card interface
• read and set configuration data from SD card (
• should have a #define switch
• if SD card or data error, then fail to start up

Acceptance Test

• Read and set sample config data
• handle error (fail to startup) on data error

add document that lists pin assignments based on 1.0/v6 board.

TNC compatible serial interface (KISS or AGW)

Blue tooth interface for configuring and stream messages

Desired features

• create central log function for outputting info messages to LCD and serial port
• e.g log(LEVEL,"serial text","lcd text")
• LEVEL=debug,error,out
• timestamp should be added to serial text messages (no timestamp, then zeroed out field should be used).
• LCD messages can be scrolled up
• either text field can be set to NULL (results in no output)

reviewing shielding and enclosure recommendation for board
add shielding between RF and Mega
chokes/ferrite beads for power lines?
ground plane areas for soldering sheilding

Add Arduino code to set PD logic pin to HIGH for operation, and low for power down.
Current behavior for 1.0 will be to set and leave it HIGH.
Pin Number should be set in the #define.

add APRS transmission of course and speed update messages.

add a dupont header for programming the Mega2650 (rewire to fit FDTI to USB adapter)

investigate replacing microSD board with smaller board

1. SparkFun https://www.sparkfun.com/products/13743. $5
2. https://www.pololu.com/product/2587 $5
3. https://www.adafruit.com/product/254 $7.5

Changes from the Design Review of Hardware Board

• Remove SD 2 row Headers, replace SD connector with Mini-SD card connector layout (single row pins)
  • plan to use miniSD card module, relocate on board with no overhang
• PTT - don't need mosfet switch, just use arduino pins (reverse logic)
• add add' bypass cap near voltage regulator ic
• make sure power traces are sized for 1 amp
• review power input terminal screw block - is the orientation correct? review Poloru to see if clamp down wago connects can be used.
• group interfacing pins (gps, lcd, etc) into common blocks 1x or 2x rows. use std sizes
• add gnd pads to led, to allow board mounting of leds (blinkenlights)
• add power indicator led (board or remote)
• tie in ground pour and corner holes ground planes.
• add test pads to the board.
• review 818 pads to make sure ground pads work for DRA or SA models.
• make sure the Mega2560-core pins to usb cable have clearance to be connected after installed.
• mounting holes for LCD display.
• alternatives to using SD card for configuration.

Add ability to set PTT logic to ON=true, or OFF=false, or the reverse. Hardware design updated to remove Mosfet Switch, so the default is now ON=LOW, OFF=HIGH on PTT pin.

add preflight checks before startup (confirm txcr is attached, gps is working, etc) .

Desired Feature

• "Smart Beacon" mode, which will adjust the transmit timing based on how fast the position is changing from the GPS.

change the current position change algorithm from use string compares to using an MPH threshold.
use the TinyGPSplus "distanceBetween" function to calculate distance, and calculate the position change in miles per hour. The position_trigger is now determined by when the MPH threshold is exceeded.

Add a interface button

should detect press, long press, double press

press: backlight toggle (maintain backlight off mode after timer expires)

long press: setting display menu
press: scroll thru settings

double press: beacon now! mode

change GPS speed back to 9600
reprogram GPS

Add backlight control for LCD display

Turn backlight on (button)?
Turns off backlight after XX seconds

add reading and verifying txcr responses (the DRA818 library doesn't do this, it fires and forgets).

Complete all the config.txt file parameter settings

• reducing the LEDs from 4 to 1 (maybe zero, and just the Arduino LED)
• remove the 2x3 ISCP pins (jp13)
• remove the 2x2 extra power out pins. (jp7and9)
• remove the extra IO pins (JP10/11/12) (maybe keep 2 or 3)
• remove the i2c 3 axis pins (JP4)
• remove LCD mounting holes remove the LCD i2c and pwr pins ( JP2 and JP8)
• remove the tactile switch
  Most of these were not being used, so it frees up a lot of board space (and power consumption, in the case of the LEDs). I can reduce the board width about 20mm with these changes. (from 10x8cm to 10x6cm. I may leave some of these as holes if I have room. A lot of these boards are used without the LCD anyway, and its a significant savings for power consumption.

PCB - Adding additional space for the SMD voltage regulator ground pad and a thru hold to make it easier to solder on the VR

Desired Features:
add LED pin control for GPS fix (fix=on)
confirm and test TX/RX LED pins working

Changing the wiring pins (for the GPS, Power Input and Output, and serial port to JST-XH style connectors.

Add header (2 wire d+/d-) JST-XH header for connecting USB cable
also look at option to put USB cable on the board directly (micro-usb)

Hi,

Could you please share the Gerber file for the PCB so one could have the board made?

Thank you.

the board layout for V6 was incorrect - Jmp 16 and 19 were swapped on the layout. This breaks the LED pin assigments for TX and RX led pins. Luckily, this can be fixed by reassigning TX to pin D49 and RX to pin D46, and changing the LibAPRS to use DDR pins L0 for TX and L3 for RX.

PCB - review spacing for resistors, and adding larger solder rings

Update the Beaconing Algorithm
show allow multiple types: fixed interval, "notsosmart" beacon mode, and provisional pathing

APRS location packets are missing leading zeros for lat/long updates, for latitudes less than 10, and longitude less than 100. The APRS 1.0 spec implies, but does not specify leading zeros for these values.

example (note the leading space char in the longitude value in the second packet:
2017-07-06 15:48:37 PDT: KK6DF-3>APZCCR,WB7GR-3*,WIDE2-1,qAR,WB7GR-10:=4110.55N/10404.64W>/A=005139LART1 Tracker V1
2017-07-07 09:27:52 PDT: KK6DF-3>APZCCR,KC0MWM-1,WIDE1,DELPHS,WIDE2*,qAR,KI0AU-1:=4049.29N/ 9818.88W>/A=001975LART1 Tracker V1

repeatable: yes

proposed solution: leading zeros added to lat/long packet values.