In a push-to-talk device having two processors where one of the processors
is a radio chip and one of the processors is a microprocessor, a method
and apparatus for synchronizing the microprocessor and the radio chip
includes the steps of checking the status of a radio push-to-talk key on
the radio chip when a user push-to-talk button is turned on or off on the
microprocessor; if the user push-to-talk button is on and the radio
push-to-talk key is off, performing the steps of sending a command to the
radio chip to turn on the radio push-to-talk key; and waiting for a
response from the radio chip, and if the response indicates the radio
push-to-talk key is on, remaining in this synchronized state, otherwise
repeating the sending and waiting steps; if the user button is off and
the radio push-to-talk key is on, performing the steps of sending a
command to the radio chip to turn off the radio push-to-talk key; and
waiting for a response from the radio chip, and if the response indicates
the radio push-to-talk key is off, remaining in this synchronized state,
otherwise repeating the sending and waiting steps; if the user
push-to-talk button is off and the radio push-to-talk key is off,
remaining in this synchronized state; and if the user push-to-talk button
is on and the radio push-to-talk key is on, remaining in this
synchronized state.