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DM102 Freq In/Out

Frequency meter and generator.

The frequency meter will measure frequencies between 1 Hz and 36 MHz (3.3V in).

Outputs include square waves and short pulses (both 1 Hz to 18 MHz), as well as a fixed crystal output (8 MHz). The rotary encoder sets the output in increasingly coarse steps.

Usage

  1. Connect any of the IO-1 / IO-2 / IO-3 outputs as needed (3.3V levels).
  2. Turn the knob to adjust the frequency between 1 Hz and 18 MHz.
  3. Press the knob to enable / disable the IO-1 and IO-2 outputs.
  4. Connect IO-4 to any 3.3V logic signal to be measured.

Frequency adjustments are limited to these 74 values: 1..9 Hz, 10..90 Hz, 100..900 Hz, 1..9 kHz, 10..90 kHz, 100..900 kHz, 1..9 MHz, 10 / 12 / 14 / 18 MHz. Some of the higher frequencies are approximate (they are all derived from the µC's 72 MHz system clock).

Connections

Left I/O Right Bus
IO-1 Fout BUS-A LIN
IO-2 Pulse BUS-B N/C
IO-3 8 MHz BUS-C N/C
IO-4 Fin BUS-D N/C
GND +3.3V +5V GND
√ N/C IN N/C

Board

This module was manually constructed using a 7x3 cm proto board.

Components

Schematics

Software

TBD