Texas Instruments CC2541EMK Application Guide

TI CC2540 Bluetooth low energy Sample Applications Guide v1.4.1 SWRU297 Version 1.4.1
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Copyright © 2011-2015 Texas Instruments, Inc
6.2.8 Neglect Timer
This device has a compile time option that allows the sensor to terminate a connection if it sees
no user input for 15 seconds. In the context of this application, this means that after the device
has connected and notifications are disabled, the application starts a timer. This timer is restarted
whenever a read or write request comes from the peer device, and is disabled while notifications
are enabled. If the value USING_NEGLECT_TIMEOUT is set to FALSE at compile, then this
timer is permanently disabled at runtime.
7 Glucose Collector
This sample project implements a Glucose Collector. The application is designed to connect to
the glucose sensor sample application to demonstrate the operation of the Glucose Profile.
7.1 Project Overview
The Glucose Collector project structure is very similar to that of the SimpleBLECentral project.
The APP directory contains the application source code and header files. The project contains
one configuration, CC2540EM Master, using the SmartRF05EB + CC2540EM hardware platform.
7.1.1 User Interface
The SmartRF05EB joystick and display provide a user interface for the application. The joystick
and buttons are used as follows:
 Joystick Up: If not connected, start or stop device discovery. If connected to a glucose
sensor, request the number of records that meet configured filter criteria.
 Joystick Left: Scroll through device discovery results. If connected to a glucose sensor,
send a record access abort message.
 Joystick Center: Connect or disconnect to/from the currently selected device.
 Joystick Right: If connected, request records that meet configured filter criteria.
 Joystick Down: If connected, clear records that meet configured filter criteria. If not
connected, erase all bonds.
The LCD display is used to display the following information:
 Device BD address.
 Device discovery results.
 Connection state.
 Pairing and bonding status.
 Number of records requested.
 Sequence number, glucose concentration, and Hba1c value of received glucose
measurement and context notifications.
7.1.2 Basic Operation
When the application powers up it displays "Gluc. Collector" and the BD address of the device.
Press Joystick Up to start device discovery. When discovery completes the number of devices
found will be displayed. Press Joystick Left to scroll through the devices.
To connect to the selected device press Joystick Center. The connection status will be displayed.
Once connected, the application will attempt to discover the Glucose service and Device
Information service on the peer device. Since the Glucose profile required security the application
will also initiate bonding. When the bonding is complete, other operations such as reading or
erasing records can be performed described in the previous section. It is important to note that,
due to the input / output capabilities of the keyfob, we have to use a fixed password in order to
achieve authenticated pairing. We have set the I/O capabilities of the keyfob to display only. The
idea is that the keyfob will display the passcode and it will be entered on the SmartRF. However,
because the keyfob and SmartRF don’t actually have these I/O capabilities, we hard code the
passcode in the sensor and collector projects to be 19655.

Texas Instruments CC2541EMK Specifications

General

Brand	Texas Instruments
Model	CC2541EMK
Category	Microcontrollers
Language	English