Which Stratus Tap Is Right for You?
Three serial analyzers. Different jobs. This page helps you pick the right one in under a minute.
Quick Picker
- Basic RS-232 monitoring, up to 9,600 bps → EZ-Tap ($265)
- RS-232 above 9,600 bps, or microsecond timing + handshake capture → EZ-Tap Pro ($375)
- RS-422, RS-485, multi-protocol, or mixed-voltage work → Versa-Tap ($450)
Side-by-Side Comparison
| Feature | EZ-Tap | EZ-Tap Pro | Versa-Tap |
|---|---|---|---|
| Price | $265 | $375 | $450 |
| Protocols supported | RS-232 | RS-232, 3.3V/5V TTL | RS-232, RS-422, RS-485, 3.3V/5V TTL |
| Voltage switching (RS-232 ↔ LVTTL, no adapter) | — | Yes | Yes |
| Max baud rate | 230,400 bps | 1 Mbps | 2 Mbps |
| Auto comm parameter detection | — | Up to 921,600 bps | Up to 921,600 bps |
| Microsecond hardware time-tagging | — | Yes | Yes |
| Captures all 6 handshake lines | — | Yes | Yes |
| Synchronous HDLC support | — | — | Yes |
| Connection type | Dual COM port (DB9) | Dual COM port (DB9) | Screw terminals |
| Host interface | USB | USB | USB (Mini-B cable included) |
| Free EZ-View software | Yes | Yes | Yes |
| Docklight compatible | Yes | Yes | Yes |
| Custom .DLL API support | — | Yes | Yes |
| Windows support | 2000 – 10 | 2000 – 10 | 2000 – 10 (x32/x64) |
Why These Differentiators Matter
Microsecond hardware time-tagging (EZ-Tap Pro & Versa-Tap)
At baud rates above roughly 9,600 bps, software-only timestamps can't reliably determine which message arrived first — hardware-to-software acquisition delays scramble the ordering. EZ-Tap Pro and Versa-Tap timestamp every byte and handshake event in hardware at microsecond precision, so you can accurately reconstruct transmit/reply sequences even at 1 Mbps and above. This is why we recommend Pro or Versa-Tap for any serial debugging above standard rates.
RS-232 / LVTTL voltage switching (EZ-Tap Pro & Versa-Tap)
Modern hardware designs often mix legacy RS-232 with 3.3V LVTTL microcontrollers or 1.8V/2.5V embedded systems. No other passive tap on the market handles voltage-level conversion in a single device — competitors require separate adapter hardware. EZ-Tap Pro and Versa-Tap switch between standard RS-232 (±5V) and LVTTL voltage levels (1.8V / 2.5V / 3.3V / 5V) without any external converters.
Automatic comm parameter detection (EZ-Tap Pro & Versa-Tap)
Connect to an unknown serial link and the tap figures out the baud rate, data bits, parity, and stop bits automatically — up to 921,600 bps. No more trial-and-error settings in your monitoring software. This single feature is one of the biggest reasons customers stop calling support on day one.
Capture of all 6 RS-232 handshake lines (EZ-Tap Pro & Versa-Tap)
Most monitoring tools only capture data on the TX/RX lines. EZ-Tap Pro and Versa-Tap also capture state changes on all six RS-232 control lines (DTR, DSR, RTS, CTS, DCD, RI), giving you full visibility into hardware flow control, modem signaling, and legacy phone-line communication. Essential when you're debugging timing-sensitive handshake protocols or troubleshooting why two devices aren't talking.
Synchronous HDLC support (Versa-Tap only)
Most passive taps only handle asynchronous serial data. Versa-Tap captures synchronous HDLC frames in addition to RS-232/422/485, making it the right choice for industrial protocols, telecom equipment, and any application using bit-oriented framing.
Which One Is Right for You?
EZ-Tap — the budget workhorse
EZ-Tap is the no-frills, plug-and-go option for monitoring RS-232 traffic at standard baud rates. It uses a traditional dual COM port approach, works with EZ-View and most third-party serial monitoring software, and gets the job done at the lowest price point in the lineup. See EZ-Tap →
EZ-Tap Pro — when timing matters
EZ-Tap Pro adds what software-only solutions can't deliver: exact microsecond hardware time-tagging of every data byte and handshake event, plus capture of state changes on all six RS-232 control lines (DTR, DSR, RTS, CTS, DCD, RI). Supports baud rates up to 1 Mbps and switches between RS-232 and LVTTL voltage levels without an adapter. If you're debugging handshake timing, race conditions, or mixing modern 3.3V hardware with legacy RS-232, this is the right tap. See EZ-Tap Pro →
Versa-Tap — the multi-protocol option
Versa-Tap handles RS-232, RS-422, RS-485, and TTL voltages in a single device, with synchronous HDLC analysis and baud rates up to 2 Mbps. The screw-terminal interface makes it a fit for industrial, automation, and embedded environments where you don't have clean DB9 connections to work with. See Versa-Tap →
Frequently Asked Questions
What's the difference between EZ-Tap and EZ-Tap Pro?
EZ-Tap is a basic dual-COM-port tap for monitoring RS-232 traffic up to 230,400 baud. EZ-Tap Pro adds three things EZ-Tap can't do: exact microsecond hardware time-tagging of all data and handshake events, capture of state changes on all six RS-232 control lines, and support for baud rates up to 1 Mbps. If you need precise timing or visibility into flow control, you need Pro.
Can I use Versa-Tap on RS-232?
Yes. Versa-Tap supports RS-232 in addition to RS-422, RS-485, and 3.3V/5V TTL. It's the right choice if you work across multiple protocols and want a single device that covers all of them.
Can I switch between RS-232 and LVTTL (3.3V) voltage levels?
Yes — on EZ-Tap Pro and Versa-Tap. Both modules let you switch between standard RS-232 (±5V) and LVTTL (0–3.3V) voltage levels without any hardware adapters or external converters. This is especially useful in modern designs that mix legacy RS-232 equipment with 3.3V microcontrollers or embedded systems — a capability no other passive tap on the market offers.
Do these taps interfere with the connection I'm monitoring?
No. All Stratus taps are passive, meaning they sit in line with your serial link and observe traffic without injecting signals or interrupting communication. The devices on either end behave as if the tap isn't there.
What operating systems are supported?
Windows 2000 through Windows 10 for all three products. Versa-Tap drivers support both 32-bit and 64-bit builds.
What's included with each tap?
All three include USB drivers and free EZ-View monitoring software. Versa-Tap additionally ships with a 6-foot Mini-B USB cable.
Can I use third-party monitoring software?
Yes. All three products work with Docklight, and EZ-Tap is also compatible with most third-party dual COM port serial monitoring programs. EZ-Tap Pro and Versa-Tap additionally support custom application development through Stratus Engineering's .DLL-based Windows API — contact us for examples and details.
Where are Stratus taps made?
Designed and supported in San Diego, California. Used by engineering teams at Microsoft, Motorola, Raytheon, Lockheed Martin, and dozens of other companies worldwide.
