Intended Use

The He/O2 Printer Cable connects the Divesoft He/O2 Analyzer to a compatible label printer.

The cable is powered directly by the analyzer, as indicated by the POWER LED.

A toggle switch on top of the connector allows the printer to charge the analyzer. Active charging is indicated by the CHARGE LED.

Note: When using a battery-powered portable label printer, keep charging turned OFF to conserve the printer's battery life.

System Requirements & Compatibility

✅ Compatible Devices

• He/O2 Analyzer: compatibility varies by Hardware (HW) and Firmware (FW) versions:
  • HW 2.3 and earlier ... not supported
  • HW 2.4 & 2.5 ... FW 2.41.0 or newer
  • HW 4.x ... FW 3.43.0 or newer
  • You can update your He/O2 FW using the online tool Divesoft Center
• Printer: ZPLII-compatible Zebra Label Printer (e.g., Zebra ZD421 series).
• Serial Module: Zebra RS-232 Serial Interface Module installed in your printer.
  • ZD421 models: Requires Zebra module P1112640-016.
  • Older models: Search for the dedicated Zebra serial module for your specific printer model.

❌ Incompatible Devices

• SOLO analyzers are NOT compatible with cable #7312.
• DNA and ECHO operate via Bluetooth and supports printers using the Divesoft Mobile App.

Setup

1. Power Off: Turn off both the He/O2 analyzer and the Zebra printer before making connections.
2. Connect Auxiliary Port: Plug the red multi-pin connector into the Auxiliary Attachment Connector on your He/O2 Analyzer.
3. Connect Serial Port: Plug the black DB9 connector into the RS-232 Serial Port on the rear of your Zebra printer. Tighten the side thumbscrews to secure it.
4. Power On: Turn on both devices.
5. Configure your Analyzer
   • On your He/O2 Analyzer, navigate to: MENU ➔ PRINTER
     
     

     Setting Parameter	Recommended Value	Description
     Printer Mode	ON	Enables printer communication. Pressing OK during analysis prints a label.
     Diver Name	Custom (Max 8 chars)	Optional name printed on the header of every label.
     Resolution	Match printer DPI	Select 203 DPI, 300 DPI, or 600 DPI (the ZD421t comes in 203 as well as 300 DPI variants).
     Dimensions	Match label media	Set width and height to match label size (Maintain a 2:3 aspect ratio).

NOTES

1. Once setup is complete, restart the analyzer to apply your changes (eg. when changing label resolution).
2. If the PRINTER menu does not appear, verify that your firmware (FW) version meets the minimum requirement.
3. When Printer Mode is enabled ON, data output is routed to the auxiliary port, which temporarily disables standard USB output.

Printing

1. Analyze Gas: Connect your gas cylinder and take a measurement as normal.
2. Trigger Print: Press the OK button on the analyzer while measuring.

3. Result: The analyzer freezes the reading on screen and instantly sends the formatted print job to your Zebra printer.

Docs & Links

Did you know that most printers support printing over the bluetooth as well ?

For more information, including durable, diver-resistant labels see our blog.

Divesoft Blog - Cylinder Labeling

Resupply the consumables through the Divesoft Eshop

Try the Divesoft Toolkit

Technical Specifications

HE/O2 Analyzer Printer cable - QUICK REFERENCE

Date of issue: 04 August 2026
HW 1.0, FW 2.41.0
Author: Jakub Hečko
Published by Divesoft s.r.o.