Hello,
I was wondering if anyone could tell me if it is possible to interface the LDR3x.V2.1 controller to an Arduino or RaspberryPi micro controller to command the volume. I'm looking to aggregate control of an attennuator, input selector and display module of my choice. That being said, I would still want to retain rotary encoder control of the LDR3x.V2.1 for front panel volume adjustment.
Thanks in advance
This simple is answer is yes. You can control most aspects of the LDR3x.V2.1 board by interfacing an Arduino, or any other microcontroller, with the 3 Encoder inputs ES (switch), EA (leg A of encoder) and EB (leg B of encoder) plus of course G (common ground).
This can be done by emulating the various Encoder behaviors. The available control functions include:
Power Unit On/Off
Raise/Lower Volume
Change Input
Enable Channel Balance Adjustment Mode
Adjust Channel Balance Left/Right
Clear (Reset) Channel Balance
Mute/Unmute
Enable Remote Pairing
Start/Stop AutoCalibration
It's probably worth noting the obvious that if you already have the Encoder then you already have access to all these functions via the Encoder. Moreover you have all these functions plus 1 or 2 more obscure maintenance functions available via the Apple Remote which is inseparable from the basic LDR3x design. Last but not least the LDR3x provides input switching for up to 3 inputs via 3 on board NPN mosfet switches which can switch most any external relay to ground. There's more actually. If you pull those 3 mosfets and load a different version of the firmware, those same 3 outputs that drive the mosfets can be used as 3 bit number to switch up to 8 input devices if interfaced with an appropriate 3-to-8 decoder chip.
