TI Design and Software Examples
The learning mode example code provided uses a Timer A capture input to receive an IR signal stripped
of its 38-kHz carrier, and records the edge timing of the signal. This timing information is stored in FRAM
for later use. Later, when the code should reproduce the same signal for TX, it simply reads the timing
information from FRAM and uses this to set the envelope Timer values for the transmission until the
transmission is complete.
In this type of application, the device does not need to decode or understand any protocol – it simply
needs to be able to reproduce the signal on command. This code therefore supports all different ASK
encoding and protocols, allowing it to be able to copy and repeat IR commands from a wide variety of
sources like consumer television remotes.
The only limits are:
•
38-kHz carrier
This is due to the frequency of the Vishay demodulator present on the BoosterPack. This part can be
replaced and the code modified if other carrier frequencies are needed.
•
Quantity of FRAM available on the device compared to the length and number of codes to store
The code timing information is stored in FRAM, so the amount of available FRAM in your code
determines how many different codes, and the length of the codes, that can be learned.
3.1.2
Hardware
The MSP430FR4133 device has built-in IR modulation capabilities. The internal IR modulation is
configurable and flexible. It supports both ASK and FSK modulation, which allows implementation of a
variety of IR protocols. For more information on the IR modulation capabilities of the FR4133 device, see
the
MSP430FR4xx and MSP430FR2xx Family User's Guide
). For more information on how to
implement different remote control IR protocols using the FR4133 IR features, see the application report
Infrared Remote Control Implementation With MSP430FR4xx
(
).
3.1.2.1
MSP-EXP430FR4133 LaunchPad
The MSP430FR4133 device is the first device in TI’s FRAM technology platform to combine an LCD driver
and infrared modulation functions with FRAM. FRAM is a cutting edge memory technology, combining the
best features of flash and RAM into one nonvolatile memory. More information on FRAM can be found at
Device features include:
•
1.8-V to 3.6-V operation
•
Up to 16-MHz system clock and 8-MHz FRAM access
•
15.5KB of FRAM and 2KB of SRAM
•
Ultra-low-power operation
•
Low-power liquid crystal display (LCD) with LPM3.5 support
•
Two timer blocks and two serial interfaces (SPI, UART, or I
2
C)
•
RTC counter (real-time counter module) with LPM3.5 support
•
Analog: 10-channel 10-bit ADC with window comparator
•
Capacitive Touch I/Os on all GPIO pins (60) to enable touch applications
•
Digital: CRC16
For more information on the hardware and capabilities of the MSP-EXP430FR4133 LaunchPad, see the
MSP430FR4133 LaunchPad Development Kit (MSP-EXP430FR4133) User's Guide
).
15
SLAU598A – December 2014 – Revised July 2015
BOOST-IR Infrared (IR) BoosterPack™ Plug-in Module
Copyright © 2014–2015, Texas Instruments Incorporated
