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Small green circuit board with two silver DB9 serial ports and an M.2 edge connector

SMUGDESK

SMUGDESK M.2 Key M/B to Dual DB9 RS232 Serial Card PCIe 2.0 x1 2-Port COM Adapter

SKU CH-PTAM-ZT666

Adds two DB9 RS232 serial ports through an M.2 Key M/B slot using PCIe 2.0 x1 for embedded and industrial systems

  • Adds two independent RS232 COM ports via M.2 Key M/B PCIe 2.0 x1
  • Industrial-grade chip delivers anti-interference stable communication for PLCs and sensors
  • Compact small-size design fits embedded PCs and narrow chassis hosts
  • Standard DB9 interfaces compatible with terminal blocks for flexible automation wiring
  • Works smoothly with mainstream Windows and Linux for plug-and-play quick installation

M.2 Key M/B dual RS232 expansion

This PCIe 2.0 x1 adapter adds two independent DB9 serial ports through an M.2 Key M or Key B slot. It targets embedded PCs and industrial terminals that lack native COM interfaces. The board suits automation projects needing reliable serial links to PLCs, sensors or legacy equipment.

Industrial-grade chip and standard DB9

An industrial-grade serial controller provides anti-interference communication for stable data transfer in noisy environments. The compact layout fits narrow chassis and space-constrained embedded systems. Standard DB9 connectors accept terminal blocks for flexible wiring in control cabinets or test rigs.

Check M.2 slot key and OS support

Verify the host board exposes an M.2 Key M or Key B slot wired for PCIe 2.0 x1 signalling. Confirm the operating system is a mainstream Windows or Linux release that loads the driver without extra steps. Ensure physical clearance for the low-profile bracket and DB9 cables inside the target enclosure.

How it compares

Measured against everything we stock in Interface & Card Adapters, at today’s prices. Recalculated every night.

Price $40.99
Pricier than about 83% of the 354 comparable items (median $21.99).

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Specifications

No published specifications for this item yet.

Questions about this item

Does the PCIe 2.0 x1 interface limit the throughput of the two serial ports?

The card uses a PCIe 2.0 x1 bus to drive both DB9 ports; each RS232 port runs at its own signalling rate, so the single-lane link does not throttle normal serial traffic.

What M.2 slot keying and physical space does this adapter require?

It fits an M.2 Key M or Key B slot and the compact board is designed for narrow embedded chassis and industrial terminals.

How is the card installed and which step is often missed?

Insert the card into the M.2 Key M/B slot, secure it with the mounting screw, attach the DB9 cables, then install the OS driver so both COM ports appear in Device Manager or dmesg.

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