Morse Code IC Timer for Intercoms

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A Morse code IC timer for intercoms is not readily available, leading to suggestions of using cascaded 555 timers or microcontrollers like PICAXE for implementation. The goal is to modify an intercom system to recognize a simple code via a buzzer, utilizing a square wave signal. The proposed method involves setting up a switch to provide high voltage to a port pin, periodically polling the pin state to count high states for dots and dashes. The design requires the electronics to be housed within the intercom, with options for power from the intercom or a small battery. This approach aims for a compact and efficient solution for Morse code signaling.
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Is there such a thing as a morse code ic timer chip or is the only way cascading 555's or something complicated like that. Eproms and machine code is ok if that's what it takes if its cheap and easy for my pc.

Only need maybe 3/4 pulses timed.

EDIT: want to modify my intercom into a system where you press the buzzer in way that let's me in with a simple code square wavish over time.
 
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If your pc/os allows direct access to a port pins then it is pretty simple.
Set up your switch to provide the port pin high voltage.
Using the timer periodically poll the pin state.
Count the number of high states for your dash.
Count the number of high states for your dot.
Reset your pattern buffer after a certain period of inactivity.
 
Use say a PICAXE microcontroller
 
Thanks, one of those PICAXE chips should do the job nicely. I can not have my pc constanly connected to the intercom and really need the electronics in the same plastic housing. I could either power the chip from the intercom itself or use a small battery. Should be fun.
 
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