Datasheet

Command Mode

By placing the BLEFriend module in 'Command' mode (set the mode selection switch to CMD or setting the MODE pin to a high voltage) you can

enter a variety of Hayes AT style commands to configure the device or retrieve basic information about the module of BLE connection.

In order to keep from overloading your microcontroller, you can use the flow control pins. Keep the CTS pin high until you're ready for more data,

then ground it to let the Bluefruit module know you're ready for more data!

This mode uses hardware flow control! You must set the CTS pin to ground in order to enable the TXO pin, so if you're wondering why its not

responding to commands, check that CTS is being used right!

You can determine if you are in Command Mode by looking at the mode LED. It should blink three times followed by a three second pause, as

shown below:

Hayes/AT Commands

When operating in command mode, the Bluefruit LE Pro modules use a Hayes AT-style command set (http://adafru.it/ebJ)to configure the device.

The advantage of an AT style command set is that it's easy to use in machine to machine communication, while still being somewhat user friendly

for humans.

Test Command Mode '=?'

'Test' mode is used to check whether or not the specified command exists on the system or not.

Certain firmware versions or configurations may or may not include a specific command, and you can determine if the command is present by

taking the command name and appending '=?' to it, as shown below

AT+BLESTARTADV=?

If the command is present, the device will reply with 'OK'. If the command is not present, the device will reply with 'ERROR'.

AT+BLESTARTADV=?

OK\r\n

AT+MISSINGCMD=?

ERROR\r\n

Write Command Mode '=xxx'

'Write' mode is used to assign specific value(s) to the command, such as changing the radio's transmit power level using the command we used

above.

To write a value to the command, simple append an '=' sign to the command followed by any paramater(s) you wish to write (other than a lone '?'

character which will be interpretted as tet mode):

AT+BLEPOWERLEVEL=-8

If the write was successful, you will generally get an 'OK' response on a new line, as shown below:

AT+BLEPOWERLEVEL=-8

OK\r\n

If there was a problem with the command (such as an invalid parameter) you will get an 'ERROR' response on a new line, as shown below:

AT+BLEPOWERLEVEL=3

ERROR\r\n

Note: This particular error was generated because '3' is not a valid value for the AT+BLEPOWERLEVEL command. Entering '-4', '0' or '4' would

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