I'm wondering how a so called "pulse dialer" like the IN9151 (https://www.digchip.com/datasheets/parts/datasheet/237/IL9151-3N-pdf.php) internally works, meaning how it is achieved to generate a distinct amount of pulses on a button press. For example this type of IC is famously used in telephones to replace the rotary dial which generated by selecting e.g. the number 7 then seven pulses with a specific length (like 100 ms). How does this is done in the IC?
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The last page of the datasheet contains a block diagram. It runs on a clock it gets from the oscillator circicuitry, and it uses the clock to run the state machines of the internal blocks. The keyboard matrix block scan for button presses, and when a push is detected, it will generate the correct amount of pulses with timing based on the clock.
