IR-Keyboard

Arduino receiver for Infrared Keyboard FDC-3412

I got a mysterious infrared keyboard and remote labeled as FDC-3412. I cannot find any info about it.

Keyboard Protocol

By inspecting the keyboard protocol using an IR receiver I deciphered the following:

• 1 start pulse 1000 us
• 1 pause 500 us
• 14 * pulse 500us followed by one of the following
  • space 450us == 00
  • space 650us == 01
  • space 900us == 10
  • space 1150us == 11

• 14 * 2 bits = 28 bits / message.
• Bytes are in low endian order.
• There are two versions of the message:

1. key message:

• 8 bit header
• 8 bit modifier
• 8 bit code
• 4 bit checksum

2. joy message:

• 8 bit header
• 6 bit x signed value, center 0
• 6 bit y signed value, center 0
• 4 bit zero padding
• 4 bit checksum

header

• 00000010 key event
• 10000010 release key
• 01000010 repeat key
• 00100000 button1
• 01000000 button2

modifier

• 0000 0001 shift
• 0000 0010 alt
• 0000 0100 ctrl
• 0000 1000 win

x

signed 6 bit value 0 = center

y

signed 6 bit value 0 = center

checksum

Number of 1 bits in event + 2

code

• 0x50 A
• 0x35 B
• ...

Remote Joystick Protocol

The remote buttons are send with common RC-5 encoding, but the upper joystick and buttons have their own.

• Manchester encoding whith base timing of 600us
• 1 start pulse 1200 us
• 16 bits / message
• Bits are in low endian order.
  • 1 bit button 2
  • 7 bit x position as signed integer, center is 0
  • 1 bit button 1
  • 7 bit y position as signed integer, center is 0