Introduction
This document describes the BlueNRG-2N application command interface (ACI) which is provided to access the BlueNRG-2N
Bluetooth Low Energy host and controller components.
User applications, like programs running in another silicon chip, can send ACI commands to control the BlueNRG-2N device.
The ACI commands should be sent over a UART or SPI connection.
Refer to the BlueNRG-2N datasheet reference section for more information about the BlueNRG-2N device.
The BlueNRG-2N ACI command data format
UM2805
User manual
UM2805 - Rev 1 - November 2020
For further information contact your local STMicroelectronics sales office.
www.st.com
1 BlueNRG-2N ACI commands
The BlueNRG-2N ACI commands utilize and extend the standard HCI data format.
According to the Bluetooth specifications, a standard HCI packet can be:
• HCI command packet
• HCI ACL data packet
• HCI synchronous data packet
• HCI event packet
In the BlueNRG-2N, the HCI synchronous data packet is not supported, but the other three are.
HCI command packet format
• When an external device gives a command to the BlueNRG-2N, the command must be formatted in a HCI
command packet
• The BlueNRG-2N only receives the HCI command packets, but does not transmit
Figure 1. HCI command packet
• Each HCI command uses a 2-byte OpCode to uniquely identify different types of commands
• The OpCode is divided into two fields: the OpCode group field (OGF) and the OpCode command field
(OCF):
The OGF is the upper 6 bits and the remaining lower 10 bits are used by the OCF.
All HCI commands are grouped into logical groups by the Bluetooth specification and each group is assigned a
unique OGF value.
Table 1. OGF value
Group name
OGF value
Link control commands 0x01
Link policy commands 0x02
Controller and baseband commands 0x03
Information parameters 0x04
Status parameters 0x05
Testing commands 0x06
LE controller commands 0x08
Vendor specific commands 0x3F
UM2805
BlueNRG-2N ACI commands
UM2805 - Rev 1
page 2/10