We have about 4 sony remotes in the Richmond Physics Prep room.The Protocol
The following image is a waveform captured
on a TDS1002 digital storage oscilloscope on June 16, 2006 (when the "1"
button was pressed on a Sony TV remote). A PNA4602M
IR IC receiver module (38 KHz) was used. This is the same device
that is used on the Solarbotics
Sumovore Robot.
Note that in Robot Builder's Bonanza Myke Predko gives some information on the Sony TV IR remote protocol on pages 266, 270-272. His information is consistent with the waveform shown above if the interpretation of 1's and 0's is inverted from the SIRC protocol and if the bits were send MSB first rather than LSB first. It would appear that he went with what he saw on a scope without attempting to look up the actual protocol. Interpreting the signals following the actual protocol results in a more natural code sequence in which the numbered buttons have codes that are adjacent in the code space.
There are a number of sites on the web that describe the protocol used
here. The waveform above decodes as address "00001" and code "0000000".
See the following for detail:
| Sony SIRC Protocol | Keep in mind that the output from the PNA4602M IR IC receiver module is low when the carrier is received and high when nothing is received. This means that the signal from the receiver is inverted from the modulating signal in the transmitter. Some documents show the modulating signal and some show the receive signal. |
Note that in Robot Builder's Bonanza Myke Predko gives some information on the Sony TV IR remote protocol on pages 266, 270-272. His information is consistent with the waveform shown above if the interpretation of 1's and 0's is inverted from the SIRC protocol and if the bits were send MSB first rather than LSB first. It would appear that he went with what he saw on a scope without attempting to look up the actual protocol. Interpreting the signals following the actual protocol results in a more natural code sequence in which the numbered buttons have codes that are adjacent in the code space.
The following site points out that not all remotes use the exact timing specified in the protocol. This is not a big problem since there is such a big difference to the encoding of a 1 and a 0. see
More from the web:
a project idea -- HOWTO Add Remote Control Functionality to Your Alarm Clocka project idea -- A TV Remote Control Decoder
History of the TV Remote Control (zenith)
Sony TV codes ||| Lots of IR codes