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Altera_Forum's avatar
Altera_Forum
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12 years ago

Generating an ultrasonic (40 KHz) square pulse for a distance sensor with VHDL

May anyone give me a hint how to generate a square pulse with VHDL to transmit it in a transducer for a distance sensor. Thanks Francisco.
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

What's your fpga clock frequency?

a-For example, if your fclk is 50MHz, count from 0 to 50MHz/40KHz=1250.

b-add a comparator to the counter: when count<625 output is '1' else '0'.

c-register the output to avoid glitches.