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Design Steps to Using the MT Series
Default Use
1. Tie ENC_SEL high on one transcoder to put it into Default Encoder
Mode.
2. Tie ENC_SEL low on another transcoder to put it into Default Decoder
Mode.
3. Get the received address and command on the SER_IO line.
Creation of an Address and assignment of status lines
1. Take the CRT/LRN line high while the ENC_SEL line is high to enter
Create Mode.
2. The Address will be randomized for as long as the CRT/LRN line is
high (the ENC_SEL is not monitored once Create Mode has been
entered). The MODE_IND line will go high to indicate that the Address
is being randomized.
3. Release the CRT/LRN line and the MODE_IND line will begin switching
to indicate that the transcoder is ready to set status line assignments.
4. Take each line that is to be an input high within fifteen seconds.
5. Take the CRT/LRN line high again or let the transcoder time out after
fifteen seconds to exit Create Mode.
Learn another transcoder's Address
1. Take the CRT/LRN line high then low while the ENC_SEL line is low to
enter Learn Mode.
Note: When used in this manner, the device set in Default Decoder
Mode will accept all transmissions, regardless of address. For
applications where addressing is not required, this makes setup
extremely easy. For applications that need more users than can be
provided by the MT, an external controller or PC can be used to create
a larger user database. Once a remote address is learned, a valid
learned address is required for all transmissions before the transcoder
will respond.