How to choose a MicroController

Step 15 ARM microcontrollers

ARM is a company that designs microprocessor architetcures, and licenses them to manufacturers who build actual chips. The ARM is a 32bit true RISC architecture, and scales upwards to CPUs with floating point hardware and clocks speeds of several hundred MHz. If you have a palmtop, it probably contains an ARM-based chip. Your cellphone probably has an ARM based chip.

Recently, some of the manufacturers of ARM architecture chips have started offering combinations of on-chip memory and peripherals, and price, that put them into the same marketplace with 8 and 16bit microcontrollers. If you're likely to need lots of memory and performance, it may be worth looking at ARM chips. Or maybe even if you're NOT. As a professional, the possibility of having a single architecture that spans from 28pin microcontrollers to 400MHz router CPUs is attractive in many ways.

Currently, I'm finding that the breadth of the ARM space seems to generate some confusion. Putting together a tool set and development environment for a particular ARM chip can be challenging.

• [Http://www.arm.com ARM the company]
• Luminary Stellaris $1 ARMs with as few as 28 pins
• NXP (philips) LPC ARM controllers down to 48 pins and $3.
• Atmel ARM chips Atmel does ARMs as well as AVRs and 8051s
• ST M32 Cortex M3 chips Cheap chips with good peripherals, and Cute "primer" development system
• Olimex ARM development boards for Atmel, NXP, and other small ARMs
• GNUARM Homepage for the GNU ARM toolchain
• Instuctable: Pixecuter - Run Software on Matell JuiceBox

Comments

[elias.alberto]

What about the STM32F103 series? Not so hobbist-friendly because they don't have DIP packages, but they seem to be very reasonably priced (cents more than 8-bit atmega48v) and a performance beast, having 32-bit ARM cores and reaching 72 MHz. I have no idea if are there free IDEs and cheap ways of "burning" the mcus, though. Anyone ever had any experience with them?

[lakata]

We've found the highest power microcontrollers to be something like the ARM9 based STR912 (from ST MIcro). However, the development environments are pricy (unlike the Microchip MPLPAB which is free). You can use GCC, but it is painful. Decent IDEs cost between $2000 and $5000!