Small microcontrollers are often used to provide standard functions like a UART-to-UART bridge. Developing an application from scratch isn’t hard, but why do it again after it has been done before?
1. The MSP430FR2100 is the top end of the family. It adds the 8-channel, 10-bit SAR ADC with 1.5-V reference and temperature sensor.
That’s where Texas Instruments’ (TI) latest MSP430FR2000 family (Fig. 1) comes in. These devices are designed for low-cost applications, starting at just 25 cents in quantity. TI also delivers 25 applications that can be customized, thereby reducing time-to-market. They include:
Timer functions
- External RTC with backup memory
- 7-segment LED stopwatch
- External programmable watchdog timer
- Programmable system wakeup controller
- Simple RTC -based system wakeup controller
- Voltage monitor with a time stamp
Pulse-width-modulation functions
- Analog input to PWM output
- Dual-output 8-bit PWM DAC
- Servo-motor control
- Stepper-motor control
- UART software-controlled RGB LED color mixing
System functions
- ADC wake and transmit on threshold
- EEPROM emulation
- Low-power hex keypad
- Quadrature encoder position counter
- Hysteresis comparator with UART
- Multifunction reset controller
- Single-slope analog-to-digital conversion technique
- Tamper detection
- Programmable clock source
- Programmable frequency-locked loop
Communication functions
- Single-wire communication
- SPI IO expander
- UART-to-UART bridge
- UART-to-SPI bridge
These are often available as app notes, but tend to be more complete. They’re also designed to be customized. They take advantage of the peripherals in the family and can be combined as needed since they don’t typically overload the system.
The chips are built around a 16-MHz, 16-bit MSP430 core. Incorporated are 1 kB of FRAM and 512 bytes of SRAM. There’s also a 2-kB ROM that’s utilized by the collection of functions. This frees up FRAM space for additional application code.
2. The MSP-EXP430FR2433 LaunchPad kit supports TI’s BoosterPack plug-ins.
The chips work with the usual development tools for the MSP430, including TI’s Code Composer Studio (CCS). The MSP-EXP430FR2433 LaunchPad kit (Fig. 2) is available and supports TI’s BoosterPack plug-ins.