Micro-modem Software Interface Guide
The Micro-modem Software Interface Guide describes the Micro-modem's user interface. It describes modem operation, including configuration, specifies all NMEA commands and messages, and documents all features added since firmware version AUV 0.79.0.1
Micro-modem Synchronous Navigation Guide
The Micro-Modem Synchronous Navigation Guide describes using the micro-modem for passive synchronous navigation
Micro-modem Firmware
The Micro-modem firmware can be upgraded via modem serial port. There are different versions to chose, and in some cases a custom firmware build is required, with project-specific features. Custom firmware builds may be available for your application. The Micro-modem and Co-processor Firmware Programming Tutorial covers direct cable and in-situ firmware programming of the Micro-modem and Micro-modem Co-Processor.
- AUV-0.93.0.35 is the latest stable and feature-complete general firmware release. This release is for 201002 Micro-modems (i.e. v1.3, v1.3b, v1.3c or newer revisions) with bootloader version 1.3.2 or higher. 201002 Micro-modems with bootloader version 1.3.0 can be upgraded at WHOI at no cost to the user. Older 201001 Micro-modem hardware (i.e. v1.1, v1.1b) is no longer supported by WHOI. Please contact Keenan Ball at kball@whoi.edu for additional upgrade information.
IMPORTANT NOTE: If your modem is equipped with a 203004 Coprocessor you must upgrade the coprocessor firmware to PSK-0-10-0-46 or newer when you upgrade to modem firmware to AUV-0-93-34 or newer to maintain proper functionality.
Micro-modem Co-Processor Firmware
The Micro-modem coprocessor firmware can also be upgraded via the modem serial port using an application that can be installed and executed on the Micro-modem. The Micro-modem will need bootloader version 1.3.2 or higher and a coprocessor with PLD version 3. Please contact Keenan Ball at kball@whoi.edu for additional upgrade information.
- PSK-0.10.0.46 is the latest stable and feature-complete general firmware release.
- cpflash-0-01-0-03 is the downloader application for programming firmware on the Co-Processor via the Micro-modem.
IMPORTANT NOTE: If your modem is equipped with a 203004 Coprocessor you must upgrade the coprocessor firmware to PSK-0-10-0-46 or newer when you upgrade to modem firmware to AUV-0-93-34 or newer to maintain proper functionality.
Micro-modem Forward / Backward Firmware Compatibility
The Micro-modem is a continuously evolving system. Over the course of time certain standards and functionality must be updated for better performance or usability. While we strive to maintain compatibility across all generations of Micro-modem hardware and firmware, there are a few discontinuities that users should be aware of .
Here are some explanations of the most critical incompatibilities and features:
4-bit vs 7-bit addressing using FSK Rate 0:
With more and more exercises and installations requiring large numbers of modem systems in the water at one time, the 16 addresses (4-bit) that were originally available are no longer enough. Newer firmware versions now support 7-bit addressing. However, there are incompatibilities when operating a mix of hardware running 4-bit and 7-bit firmware.
A table of some of the incompatibilities is shown below.
| TX Old Firmware | TX New Firmware | |
| RX Old Firmware | OK | OK |
| RX New Firmware | Broken | OK |
The point of departure from 4-bit to 7-bit addressing is detailed in the table below:
| 4-bit Firmware Versions | 7-bit Firmware Versions |
| AUV-0-92-0-75 and older | AUV-0-92-0-76 and newer |
The typical symptom that is observed is that 16 will be added to the destination address.
PSK (all rates) compatibility:
All Micro-modem hardware and firmware versions can transmit PSK. However, the format of the PSK communication scheme has changed over time and is no longer forward or backwards compatible.
| Old PSK with FSK Cycle Init | New PSK with Integrated Cycle Init | |
| Micro-modem Firmware | AUV-0-92-0-14 or older | AUV-0-92-0-15 or newer |
| Coprocessor Firmware | PSK-0-10-0-20 or older | PSK-0-10-0-21 or newer |
In-situ programming:
All firmware versions does not support in-situ programming. All firmware versions AUV-0-92-0-28 or newer that have BRN and BSP NVRAM parameters supports in-situ programming. The Micro-modem bootloader version must be version 1.3.2 or newer to support in-situ programming.
Hardware Versions and Firmware:
The v1.1 and v1.1b Micro-modem hardware is not compatible with the v1.3 firmware and should not be upgraded nor should the v1.3 boards be downgraded.
Firmware version AUV13-0-90-39 was the first version available for the Micro-modem v1.3.
ModemTool
ModemTool is a Win32 GUI application for configuring and operating the Micro-Modem. ModemTool can generate and parse NMEA formatted Micro-Modem messages. It can schedule modem transactions and log all messages, making it useful for testing equipment and driver software.