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Serial to Bluetooth Adapter - Firefly


MPN: RN-240F, RN-240M

Delivery: Ships same or next business day

Availability: in stock

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Warranty: 1 year Comprehensive support for all products

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.

  • 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
Characters t 7 or 8 Data Bits
Connection modes Master, Slave, Instant Cable Replacement
Connectors Serial: DB9 - DTE (male) or DCE (female)
Control signals CTS, RTS
Data rates t 1200, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k, 230k
Dimensions 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
Mpn RN-240F, RN-240M
Parity odd, even, none
Power consumption
  • Idle: 1-10 ma
  • Connected: 30-50 ma
Product 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
Profiles Serial Port Profile (SPP)
Protocols Bluetooth Specfication 2.0 (with high EDR data rate!), compatible with 1.1 and 1.2
Radio Class 1 Bluetooth (up to 100 meters)
Security/Protection FHSS (Frequency Hopping Spread Spectrum) Security
Serial interfaces 374,373
Serial types 372
Stop bits 1 or 2
Storage specifications Temperature: -40°C to +85°C (-40°F to +185°F)
Temperature range Operating: -40°C to +70°C - All components rated at this range or better.


Firefly Data Sheet View (PDF)
Firefly User Guide View (PDF)
Application Note – Using a Firefly with Siemens DDC Controllers View (PDF)

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