The RC-35B is connected to the player unit via a 8 pin mini DIN. These pins have been numbered and coloured accordingly:<\/p>\n
Let’s take a look at the schematic for the RC-35B in the service manual:<\/span><\/p>\n 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.<\/span><\/p>\n 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″]<\/p>\n DIN Pin,Colour,MC34051 Pin, Description<\/p>\n 4,Purple,13,Driver 1 Out [\/table]<\/p>\n From here we see that the RC-35B\u00a0transmits on pins 4 and 6, and receives on pins 7 and 8.<\/p>\n 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: The RC-35B is still connected to the player unit; I’m merely piggybacking on to the pins.<\/em><\/p>\n It’s time to capture the serial data using RealTerm.<\/p>\n Let’s press some buttons on the RC-35B and see what we get!<\/p>\n Hmmm… doesn’t look to make much sense. I’ll clear the terminal and just press the open\/close button on deck 1:<\/p>\n 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:<\/p>\n How about when I press the open\/close button on deck 2?<\/p>\n It’s 70 bytes again for the 10 presses, but it doesn’t seem consistent \ud83d\ude41<\/p>\n 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:<\/p>\n![\"8pin\"](\"https:\/\/blog.petejefferson.co.uk\/wp-content\/uploads\/2014\/01\/8pin.png\")
<\/a><\/p>\n[table<\/code> width=\"200px\"]
\n<\/code>Pin<\/strong>,Colour
\n<\/strong><\/code>1,Red
\n<\/code>2,Brown
\n<\/code>3,Orange
\n<\/code>4,Purple
\n<\/code>5,Black
\n<\/code>6,Yellow
\n<\/code>7,Green
\n<\/code>8,Blue
\n<\/code>[\/table]<\/code><\/span><\/p>\n<\/a><\/p>\n
\n<\/span><\/p>\n
\n6,Yellow,14,Driver 1 Out (high)
\n7,Green,1,Receive 1 In +
\n8,Blue,2,Receive 1 In –<\/p>\n\u00a0RS-422<\/h2>\n
\n[table width=”500px”]
\nDIN Pin, Colour, Cable Pin, Cable Colour, Description<\/strong>
\n4,Purple,8,White,RXD(-)
\n6,Yellow,5,Yellow,RXD(+)
\n7,Green,4,Orange,TXD(+)
\n8,Blue,3,Red,TXD(-)
\n[\/table]<\/p>\n<\/a><\/p>\n<\/a><\/p>\n00 80 00 41 00 08 FC<\/pre>\n
<\/a><\/p>\nBaud Rate<\/h2>\n