Datasheet

For UART/Serial Bluefruits:

Check you have the MODE switch in CMD and the MODE pin not wired to anything if it isnt used!

If you are trying to control the MODE from your micro, make sure you set the MODE pin in the sketch

Make sure you have RXI and TXO wired right! They are often swapped by accident

Make sure CTS is tied to GND if you are using hardware serial and not using CTS

Check the MODE red LED, is it blinking? If its blinking continuously, you might be in DFU mode, power cycle the

module!

If you are using Hardware Serial/Software Serial make sure you know which one and have that set up

If using SPI Bluefruit:

Make sure you have all 5 (or 6) wires connected properly.

If using hardware SPI, you need to make sure you're connected to the hardware SPI port, which differs

depending on the main chipset.

If using Bluefruit Micro:

Make sure you change the RESET pin to #4 in any Config file. Also be sure you are using hardware SPI to

connect!