Texas Instruments (TI) new Tiva line is based on Arm's Cortex-M4F. It incorporates a range of control and communication peripherals. The Tiva C Series TM4C123x of microcontrollers was formerly known as Stellaris® LM4F MCUs (see Floating Point Cortex-M4 Sips Power). The new chips start at $2.15 and are ideal for building and industrial automation where CAN and motor control are common. It can also connect to a range of wireless interfaces from WiFi to Zigbee using external transceivers.

The 80 MHz Tiva C is based on Texas Instrument's 65nm technology (Fig. 1). It includes a floating point unit and an intelligent PWM subsystem that can easily handle most motor control chores. The system include 256 Kbyte flash plus a 2K EEPROM with wear leveling implemented in hardware. There is also a ROM with boot loader support as well as TivaWare (formally StellarisWare) with driver support as well as useful items like AES tables for encryption acceleration.

 

On the analog side, the Tiva C has a pair of 12-bit ADCs that run at 1 Msample/s. Ther are 3 analog comparators and a built-in temperature sensor. There is also an on-chip LDO voltage regulator.

The system has two watchdog timers for high reliability applications. The DMA has 32 channels allowing the CPU to handle chores other than peripheral control.

On the connectivity side there are 2 CAN interfaces, 6 serial ports, 6 I2C ports, 4 SSI/SPI ports and USB full speed with built-in PHYs. The chip supports up to 40 PWM outputs. Of these, 16 come from the PWM controller with dead-band generator, There other 24 PWM outputs from from the timers that also have CCP (capture compare) support. There are two quadrature encoders as well.

The chip can utilize as little as 1.6 µA. It has a wake up period of 500 µs.

The chip is supported by a wide range of TI and third party software tools. This includes TI's Eclipse-based Code Composer Studio. It also supports TI-RTOS (see New RTOS Builds On DSP Roots), a lightweight RTOS. The ROM-based TivaWare works with TI-RTOS, third party operating systems as well as on a barebones system. The bundled support gets developer up and running quickly often in under 10 minutes.