Month: January 2014

Denon DN-2000F MK II via USB : Part 1

In this post I will detail how to connect to a Denon DN-2000F MK II CD player’s RC-35B remote unit.

The connector

The RC-35B is connected to the player unit via a 8 pin mini DIN. These pins have been numbered and coloured accordingly:


[table width="200px"]

Let’s take a look at the schematic for the RC-35B in the service manual:


We can see that pins 1 and 3 are interconnected, as are pins 2 and 5. Measuring with a multimeter shows that these provide +5V 140mA to the RC-35B.

The other pins are connected to a Motorola MC34051, which is a dual EIA RS-422/423 transceiver. Pin 4 of the DIN is connected to pin 13 of the MC34051, pin 6 is connected to pin 14, pin 7 is connected to pin 1 and pin 8 is connected to pin 2:

[table width=”500″]

DIN Pin,Colour,MC34051 Pin, Description

4,Purple,13,Driver 1 Out
6,Yellow,14,Driver 1 Out (high)
7,Green,1,Receive 1 In +
8,Blue,2,Receive 1 In –


From here we see that the RC-35B transmits on pins 4 and 6, and receives on pins 7 and 8.


As the player and remote communicate via the RS-422 standard it should be pretty simple to sniff the conversation. I have myself a RS-422 to USB interface cable from FTDI Chip and connected it up as follows:
[table width=”500px”]
DIN Pin, Colour, Cable Pin, Cable Colour, Description

The RC-35B is still connected to the player unit; I’m merely piggybacking on to the pins.

It’s time to capture the serial data using RealTerm.

Let’s press some buttons on the RC-35B and see what we get!


Hmmm… doesn’t look to make much sense. I’ll clear the terminal and just press the open/close button on deck 1:


I pressed the open/close button on deck 1 a total of 10 times which generated a total of 70 bytes — which all seem to be same block of 7 bytes:

00 80 00 41 00 08 FC

How about when I press the open/close button on deck 2?


It’s 70 bytes again for the 10 presses, but it doesn’t seem consistent 🙁

Baud Rate

After trial and error with different Baud rates I eventually found consistency with the data received following button presses. The Baud rate is now set to 90,000 and pressing the open/close buttons on both decks generates the following:


I pressed each button 5 times. This resulted in a total of 100 bytes of data meaning that each press generates 10 bytes of data. And there is a pattern too! Let’s format the display to be a width of 10 bytes – 1 command:


It looks like the first byte is the deck number, 1 or 2, and 58 is the command for open/close. The rest of the data is just zeros; perhaps they’re not needed for this particular command.

The Commands

All of the commands from the RC-35B have been discovered and are listed here:


Byte 0, Byte 1, Byte 2, Byte 3 – Byte 9, Description

Deck,0x42,Track number,0x00,Track change

Deck,0x43,Amount,0x00,Pitch change





Deck,0x50,Mode,0x00,Time toggle (elapsed/remain)



To be continued…!