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The Modem M64 is a two-way half-duplex 64bps acoustic modem with a robust and user configurable data link.

The M64 sets a new market standard with its record-breaking physical size, low power requirement and cost. All this combined with a very useful technical specification, the M64 opens new possibilities for underwater communication in both existing and new areas.

Key specifications

  • Two-way communication

  • 64 bit per second net data link, both ways

  • Latency 1.5 – 2.5 sec

  • 200 meter range

LED Signals

  • No green light: Power is off.

  • Flashing green light (slow): Modem is trying to pair with another modem.

  • Fixed green light: Modem has sync with another modem. The LED will blink each time it receives a packet from the other modem.

Wiring interface

The tables below shows the pinning of the Modem-M64 interface.

Interface Color
Positive (10-18V) Orange
Negative/Ground Orange/White
UART TX Brown/White

Terminal Interface

The Modem-M64 has a 3.3 volt UART interface.

Settings Value
Baud rate 115200
Data parity stop 8N1
Flow control None

Libraries and code examples

Example code and libraries that can be used to communicate with the modem on the terminal interface: