Embedded Processor Watch

Editor: Jim Turley

In This Issue:

• Motorola PowerPC 8240 Gets PCI Bus
• Intel's i960VH Sprouts Single PCI Bus
• Pentium/MMX Goes Embedded
• ARC Getting Full; 30 Licensees On Board
• Industry Resources: Free DSP Info on Web
• New Embedded IC Announcements

Motorola PowerPC 8240 Gets PCI Bus

Hot on the heels of its PowerQUICC II announcement (see Embedded Processor Watch #13), Motorola has another high-end PowerPC for embedded systems. Like the recent 8260, the new PowerPC 8240 is based on Motorola's high-end 603e processor. Unlike the 8260, however, the new 8240 has full floating-point capability and a PCI bus interface.

Despite their similarity of part number, the 8240 and 8260 are quite different beasts. Whereas the 8260 (aka PowerQUICC II) is a communications controller with a PowerPC thrown in for good measure, Motorola's new 8240 is a straightforward PowerPC processor with minimal extra I/O--and none of the serial channels of the 8260. Under Motorola's new four-digit part-numbering system, the "8" indicates an integrated chip and "2" identifies a G2 (603/604) PowerPC core; the last two digits are essentially random. This nomenclature leaves plenty of room for 740/750-based chips (8300) and future G4-based devices (8400).

The 8240 integrates core-logic functions that most embedded designers can use: namely, a DRAM controller, DMA channels, and a 66-MHz, 32-bit PCI bus interface. The DRAM controller handles 100-MHz synchronous DRAMs (SDRAMs) as well as the less costly EDO (extended data-out) and fast page-mode DRAMs. Its 64-bit-wide interface includes ECC for data reliability. The internal interrupt controller handles I2O-style messaging, so the 8240 could conceivably be used in I2O disk or networking subsystems.

At the heart of the 8240 is a PowerPC 603e processor, complete with full floating-point unit (as opposed to the 8260, which is based on the slimmer EC603e core). Motorola is offering the processor at 200 and 266 MHz. Low-power customers can run the chip as slow as 100 MHz, at reduced voltage, to save power. Typical power consumption at 200 MHz is pegged at 3 W.

Motorola has set aggressive prices for its newest device. The 8240 will sell for $60 and $90 at 200 MHz and 266 MHz, respectively (both in 10,000-unit quantities), which is close to the price of the generic PowerPC 603e itself. Given the extra value of its DRAM and PCI controllers, the 8240 should quickly displace the 603e in the eyes of potential customers. Now that the 603e has left Apple's product line, its fall will be swift. The 8240 might finally lure loyal 68K customers away from the 68040 and 68060, which offer nowhere near the price/performance of the 8240 in systems that need floating-point.

Intel's i960VH Sprouts Single PCI Bus

Intel continues to push around the various ingredients in its i960 family looking for tasty combinations. The latest dish from the Intel kitchens is the i960VH, a chip that lies somewhere between the i960JT and the i960RP on the 32-bit RISC menu.

The new 'VH processor is unique among i960 chips in having just one PCI interface. Intel's four R-series processors each have dual PCI buses (upstream and downstream) for I2O applications. The other i960 incarnations, in contrast, have no PCI at all. With just one PCI bus, the 'VH is not really suitable for I2O systems, but it could be attractive for the growing legions of PCI-based embedded systems. CompactPCI backplanes, for example, could take advantage of the 'VH, as could single-board systems that use PCI for I/O interconnect.

The new i960VH is based on the J-series core, which means the chip has a 16K instruction cache, a 4K data cache, 1K of on-chip SRAM, and runs at 100 MHz. Like Motorola's new PowerPC 8240 (see previous item), the i960VH has a DRAM controller, a two-channel DMA controller, and an I2O- style messaging interface. The 3.3-V part is housed in a 324-contact PBGA (plastic ball-grid array) package.

The similarities between the i960VH and Motorola's 8240 are obvious. Both have PCI, DMA, DRAM control, I2O support, and surface-mount packages. Intel's $45 asking price for the 100-MHz i960VH (in 10,000- piece quantities) is at least $15 cheaper than Motorola's price for the 8240, but the PowerPC chip runs twice as fast (200 MHz vs. 100 MHz), has a faster PCI bus (66 MHz vs. 33 MHz), a bigger data cache (16K vs. 4K), a wider memory bus (64 bits plus ECC vs. 32 bits), and an IEEE-754 floating-point unit. Overall, the 8240 provides a better value for the extra $15, not to mention better performance. Unless embedded designers have a requirement for i960 software compatibility--or an aversion to PowerPC--the i960VH appears to be just as overpriced and underpowered as the rest of the i960 family.

Pentium/MMX Goes Embedded

Now that the chip has outlived its usefulness in the notebook PC market, Intel's Pentium/MMX is now officially an embedded microprocessor. The company has shifted responsibility for the chip from its mainstream desktop PC group to its embedded division in Chandler (Arizona), lowered prices, and extended the production life of the part by several years.

The Pentium/MMX (called the "Low Power Pentium Processor with MMX Technology" in Intel parlance) is the same chip that powered laptop PCs not so long ago. As such, it has a 64-bit bus, full FPU, dual 16K caches, and the famous x86 software compatibility. The chip is offered in 166-MHz and 266-MHz speed grades and two packages, including a new, low-profile BGA package.

The use of the term "low power" is somewhat optimistic; the chip typically dissipates 2.9 W at 166 MHz and 5.3 W at 266 MHz, according to Intel. In 1,000-unit quantities, the Pentium/MMX sells for $51 (166 MHz) or $104 (266 MHz), a bit below its former PC prices. At these prices, the Pentium/MMX is a relatively good value. Although there are many RISC processors that provide superior price/performance, none of them can compete with the wealth of software, development tools, and infrastructure that the Pentium brings with it.

ARC Getting Full; 30 Licensees On Board

Two by two, Argonaut RISC Cores (http://www.risccores.com) is slowly accumulating licensees of its 32-bit RISC architecture. Like its better- known cross-town rival ARM (http://www.arm.com), ARC has made a good business out of designing and licensing microprocessor cores to ASIC developers and semiconductor vendors. At last count, ARC had signed 30 licensees, close to the number in the ARM band.

Although the two have many similarities, ARM and ARC follow somewhat different strategies. ARC prefers to license its wares directly to users; that is, to developers of semiconductor makers who will use the ARC core in their own products. Significantly, ARC also allows-- encourages, in fact--its licensees to modify and improve on the ARC instruction set and architecture. This configurability is unusual in the processor IP industry, and gives ARC a leg up over ARM in many accounts.

Although ARC does not identify most of its licensees, Texas Instruments, Fujitsu, and newcomer eCryption Technology are among them. ARC's relatively inexpensive licensing fees and flexible and extensible architecture are its most attractive features. At this rate, ARC may soon run out of companies to license it wares to.

Industry Resources: Free DSP Info on Web

DSP technology analysis and software-development firm Berkeley Design Technology (BDTI) provides free DSP resources on its Web site. Included at the site are BDTI's composite benchmark scores, one-page overviews of many of the most popular processors used for DSP applications, the comp.dsp FAQ, and numerous papers written by BDTI staffers, including a recent ICSPAT conference presentation.

Contact BDTI (Berkeley, Calif.) at 510.665.1600, or visit the Web at http://www.bdti.com.

New Embedded IC Announcements

TLV5604 (TI) Voltage-out digital-to-analog converter has four 10-bit DACs, with 1-microsecond settling time, serial interface; in 16-lead package. Price: $4.90/1,000; Production: Now; Call TI at 800.477.8924.

TLV5614 (TI) Voltage-out digital-to-analog converter has four 12-bit DACs, with 1-microsecond settling time, serial interface; in 16-lead package. Price: $9.50/1,000; Production: Now; Call TI at 800.477.8924.

TLV5616 (TI) Voltage-out digital-to-analog converter has one 12-bit DAC, with 1-microsecond settling time, serial interface; in 8-lead package. Price: $3.15/1,000; Production: Now; Call TI at 800.477.8924.

IT8181 (ITE) Controller for LCD and VGA screens is suitable for handheld devices; bus is compatible with SH-3, SA-1100, and MIPS processors. Price: $18/1,000; Production: Now; Call ITE at 408.980.8168.

CS8420 (Crystal) Sample-rate converter for consumer and professional audio equipment has 24-bit precision, 120-dB dynamic range, and -117-dB THD. Production: 1Q99; Price: $13.90/1,000; Samples: Now; Call Crystal at 512.912.3351.