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www.lairdtech.com
Laird Technologies
BTM510/511
Bluetooth
®
Multimedia Module
6. AT+BTE=”<EIR-Data>” {Set Up Outgoing EIR Data}
This command sets up outgoing EIR (extended inquiry response) data.
Format: <EIR-Data> = printable ASCII character whenever possible, otherwise a two digit hexadecimal
with preceding ‘\’ presenting one byte. Please note that the given data is written to baseband as it
is (raw data) and no checks on the data format is performed. Hence, the user is responsible for writing
data that corresponds to the extended inquiry response data format as described in the Bluetooth
Specification Version 2.1 + EDR [1], vol3, Part C – Generic Access Profile, 8 Extended Inquiry Response
Data Format (page 1305 in the .pdf-file).
Response: <cr,lf>OK<cr,lf>
7. AT+BTE? {Query Outgoing EIR Data}
This command prints the outgoing EIR data that is currently set up
Response:
<cr,lf>
<EIR-Data>
<cr,lf>OK<cr,lf>
Secure Simple Pairing (SSP)
Secure Simple Pairing (SSP) has been introduced since Bluetooth 2.1 + EDR. It aims to increase the security
provided by a Bluetooth link whilst making the pairing process more user friendly.
There are white papers about SSP available through the Internet (provided by the Bluetooth SIG and other com
-
panies), explaining the mechanisms and backgrounds of SSP. They can be found by searching the Internet for,
e.g., “Bluetooth Secure Simple Pairing”. Please familiarize with those documents to get a better understanding
of SSP and the following settings.
1. Security Level (S320)
The security level is defined in the BT2.1+EDR specification [1], vol3, Generic Access Profile (Table 5.7).
There are 4 Levels providing different levels of security:
Security Level
Characteristics
Comment
Level 3
• MITM protection (MITM = “Man in the
Middle” attack)
• Encryption
• User interaction
High security
Level 2
• No MITM protection
• Encryption
Medium Security
Level 1
• No MITM protection
• (No) Encryption (1)
• Minimal user interaction
Low Security
Level 0
• No MITM protection
• No Encryption
• Minimal user interaction
Permitted only for service
discovery
(1) Although encryption is not necessary for security level 1, encryption will always be enabled
because this specification mandates encryption for all services other than SDP (service discovery).
Table 3.3: Security Levels
The security level is defined by S Register 320 and is referenced at boot time only. Hence the register
must be saved by “AT&W “ and the module must be power cycled (or “ATZ”) subsequently.
S320 = 3 will overwrite the setting of S Register 322 (enable MITM).
The security level will remain the same until next power cycle and is valid for all profiles and services
of the module. For SDP (service discovery profile), security level 0 is always assigned internally.
AT COMMAND SET
REFERENCE
