Serial to Bluetooth Adapter - Firefly: USB Power Cable - DTE (Male Pins)


Regular price: $87.00

5.0 stars 5.0 (5) See customer reviews


MPN: RN-240M

Manufacturer: Grid Connect Inc.

Stock Status: In stock

Delivery: Ships same or next business day
Qualifies for Free shipping
Limited quantities available
DTE maximum 2 units per order
DCE maximum 10 units per order

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Product Information

Product Description

The Firefly is a Bluetooth to RS232 serial adapter. It attaches to a RS232 serial port making it a Bluetooth Class 1 wireless connection, capable of transmitting your serial data up to 100 meters (330 feet) away.

You can use the Bluetooth Firefly with another Firefly in "cable replacement mode" to make your RS232 cable wireless, or you can pair it with a BluePort XP (battery powered), FirePlug(USB serial adapter) or BluePlug (USB adapter). The Firefly Bluetooth serial adapter may also be paired with any other Bluetooth device that supports Bluetooth SPP (Serial Port Profile). Note that many devices with built-in Bluetooth (e.g. PC's, Laptops, Handhelds and phones) utilize Bluetooth Class 2 radios, which only has a range up to 10 meters, so if you use a Firefly with a Class 2 device, you will only get the effective range of the Class 2 device and not the Firefly. 

The Firefly supports the latest and greatest Bluetooth specification 2.0 (which provides faster Enhanced Data Rate (EDR) and lower Bit Error Rate (BER)), but is also compatible with devices supporting the older 1.x specifications.

The Firefly has dip switches to make set-up of the most common serial baud rates quick and easy. It also supports "AT" commands which allow you to change the firefly settings with messages sent through the serial port.


Order Summary



Power Supply


Manufacturer Part # (MPN)

GC-BT-FIREFLY-DCE-110 110V - U.S./North America DCE (Female Holes) RN-240F
GC-BT-FIREFLY-DCE-220 220V - Europe (Except U.K.) DCE (Female Holes) RN-240F
GC-BT-FIREFLY-DCE-NOPS No Power Supply DCE (Female Holes) RN-240F
GC-BT-FIREFLY-DCE-USB USB Power Cable DCE (Female Holes) RN-240F
GC-BT-FIREFLY-DTE-110 110V - U.S./North America DTE (Male Pins) RN-240M
GC-BT-FIREFLY-DTE-220 220V - Europe (Except U.K.) DTE (Male Pins) RN-240M
GC-BT-FIREFLY-DTE-NOPS No Power Supply DTE (Male Pins) RN-240M
GC-BT-FIREFLY-DTE-USB USB Power Cable DTE (Male Pins) RN-240M


  • DIP switches for 9600/115200 Baud Rate (other baud rates available with AT commands), Auto Master, Auto Discover and factory reset
  • AT Commands for easy setup through serial port (use Windows Hyperterminal or similar)
  • No software or drivers required
  • OEM versions available
  • Plastic Housing

Documents and Drivers


Firefly Datasheet

Firefly User Guide

Application Note – Using a Firefly with Siemens DDC Controllers


Characters T

7 or 8 Data Bits

Connection Modes

Master, Slave, Instant Cable Replacement


Serial: DB9 - DTE (male) or DCE (female)

Control Signals


Data Rate

1200, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k, 230k


3.0" x 1.3" x .9"

Flow Control

Hardware (RTS/CTS) or None

Included in Box

  • AC Power Adapter, 1A @ 5VDC (USB Power cable available)
  • CD with Manual

Indicators LED

  • Transmit/Receive (TX/RX) Data
  • Power
  • Connection Status


RN-240F, RN-240M


odd, even, none

Power Consumption

  • Idle: 1-10 ma
  • Connected: 30-50 ma

Power Supply

  • Pin 9 of serial DB9 connector - must be regulated to 4-11 VDC
  • Wall Supply: 5 VDC @ 1A, Plug size (1.3 x 3.5 x 9.5 mm)
  • USB Cable (draws power from USB Port)

Product Weight

0.6 oz - Approximate, Without Power Supply


Serial Port Profile (SPP)


Bluetooth Specification 2.0 (with high EDR data rate!), compatible with 1.1 and 1.2


Class 1 Bluetooth (up to 100 meters)


FHSS (Frequency Hopping Spread Spectrum) Security

Serial Interfaces


Serial Types


Stop Bits

1 or 2

Temperature Range

  • Storage: -40°C to +85°C (-40°F to +185°F)
  • Operating: -40°C to +70°C - All components rated at this range or better.

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