Based on the need for more processing performance and more than 64 Kbyte memory, engineers in many market segments are considering upgrading from 8-bit or 16-bit microcontrollers (MCUs) to 32-bit products. Once users arrive at this point, industry standard architectures instead of a proprietary approach and C programming capability instead of assembly language are very important. Responding to this trend, Texas Instruments (TI) recently announced the TMS470 platform of ARM7-based general-purpose processors.
Using the 32-bit ARM7 Thumb extension debug module multiplier interface (TDMI) core (ARM7TDMI®), TMS470 MCUs offer up to 60MHz of performance for general-purpose applications that include industrial, medical instrumentation, consumer electronics, and data processing.
TI has been shipping the TMS470 in volume to automotive customers for over five years, according to Will Rickett, TI's TMS470 MCU catalog worldwide marketing manager. He says, "Now we are taking the same technology and bringing it to the mass market."
The standard instruction set in the TMS470 is 32-bit, but the Thumb extension is a 16-bit instruction set, so the designer can choose to compile either in the 16-bit mode to optimize for a 25 to 30 percent reduction in code size or in the 32-bit mode to optimize for performance that is about 30 percent higher. With the code compiled within the modules, the designer can switch between optimizing the portions of code for performance or size. The CPU core automatically decompresses the 16-bit instructions without sacrificing CPU performance.
Performance Plus: Texas Instruments
adds powerful peripherals to ARM 7
The key to the TMS470 capability is up to 60 MHz performance, 64K to 1 Mbyte
Flash, 4 to 64 Kbyte RAM, and an extensive peripheral library, which includes a
programmable 32 channel high-end timer (HET), analog-to-digital converter (ADC)
with a 1.5 msec conversion time, CAN controller, serial peripheral interface
(SPI), and serial communications interface (SCI). Flash memory can provide
slower access, so TI uses a pipelined mode to download a number of instructions
at a time to realize the full performance rating of 60 MHz single instruction
execution per clock.
Based on its ARM 7 Open Architecture, the TMS470 has full third party support. A Kickstart Development Kit, TMS-FET470A256, is available for $399.
In quantities of 1,000, pricing starts at $4.95 for the
TMS470R1A64, A128, and A256, which have 64 Kbytes, 128 Kbytes, and 256 Kbytes of
Flash memory and run at 48 MHz. The 60 MHz TMS470R1A288, A512, A768, and A1024
will be available by midyear starting at $8.95 for 1,000 quantities.