BD (Interface Data Rate)

This command applies to the XBee/XBee-PRO SX RF Module.

Sets and reads the serial interface data rate (baud rate) between the device and the host. The baud rate is the rate that the host sends serial data to the device.

When you make an update to the interface data rate, the change does not take effect until the host issues the CN command and the device returns the OK response.

The BD parameter does not affect the RF data rate. If you set the interface data rate higher than the RF data rate, you may need to implement a flow control configuration.

The range between standard and non-standard baud rates (0x9B - 0x4B0) is invalid. The range between 0x2580 and 0x4AFF is also invalid.

Non-standard interface data rates

The firmware interprets any value within 0x4B0 - 0x2580 and 0x4B00 - 0x1C9468 as an actual baud rate. When the host sends a value above 0x4B0, the firmware stores the closest interface data rate represented by the number in the BD register. For example, to set a rate of 19200 b/s, send the following command line: ATBD4B00.

Note When using XCTU, you can only set and read non-standard interface data rates using the XCTU Serial Console tool. You cannot access non-standard rates through the configuration section of XCTU.

When you send the BD command with a non-standard interface data rate, the UART adjusts to accommodate the interface rate you request. In most cases, the clock resolution causes the stored BD parameter to vary from the sent parameter. Sending ATBD without an associated parameter value returns the value actually stored in the device’s BD register.

The following table provides the parameters sent versus the parameters stored.

BD parameter sent (HEX) Interface data rate (b/s) BD parameter stored (HEX)
0 1200 0
4 19,200 4
7 115,200 7
1C200 115,200 1B207

Parameter ranges

0 - xA (standard rates)

0x4B0 - 0x1C9468 (non-standard rates; 0x2581 to 0x4AFF not supported)

Parameter Configuration (b/s)
0 1200
1 2400
2 4800
3 9600
4 19200
5 38400
6 57600
7 115200
8 230400
9 460800
10 921600

Default

3