To record my FPV videos I bought such 2.5″ DVR recorder on eBay:
There are no buttons on the recorder. All controls are done using the IR remote control. Dealing with the remote isn’t very handy out in the field, so I decided to add three extra buttons for record, stop and preview:
Very simple: An AVR ATtiny25 generates the IR commands which are injected right after the IR receiver. All you need is just 3 push buttons, an ATtiny25 and one 1 KOHmresistor.
The ATtiny25 needs run on the internal RC oscillator with 8MHz, so fuses needs to be configured the right way.
Download the schematic and firmware:
Schematic for the 2.5" DVR modification using an ATtiny25.
Firmware for the ATtiny25 used in the 2.5" DVR modification.
Emulated the IR commands for REC, STOP and PREVIEW.
By the way, how my ground station looks right now:
The new 28 channel receiver combined with the modified 2.5″ DVR. Everything is powered by a 3S LiPo battery.