I had this firmware working a few years ago in a motorcycle application. The circuit is modified from the original design in that it uses the ShareGPS Android app on a smartphone transmitting to an HC-06 bluetooth transceiver with the HC-06 TXD pin wired to the RX pin of an Arduino Nano. The Nano is then connected to a Friendcom FC-301D transceiver which requires a ground on its PTT pin to transmit, so it requires reversing of the HX1 PTT HIGH and LOW parameters. I just tried to revive this project with the latest version of Trackuino but the radio will not transmit. The smartphone is paired to the HC-06 and ShareGPS is showing a 3D fix and is connected to the HC-06 as indicated on the Connected tab on the ShareGPS screen and the HC-06 LED changes from blinking to steady state . The radio’s transmitter works if I manually ground the PTT pin. I then took the radio out of the circuit and monitored the D4 pin of the Nano but it always shows 5V, never going near 0. I can toggle the D4 voltage using a modification of the blink program, so I know that is ok. I was looking through the code but can’t locate the line(s) that trigger the PTT function. How else can I troubleshoot this?
73,
Gary
VE6UQ