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NEW PRODUCT NEWS—edited by Harv Weiner

High-Speed Microcontroller

The DS89C420 high-speed microcontroller is compatible with the 8051 and achieves peak processing speeds of 50 MIPS at a maximum clock speed of 50 MHz.

The 8-bit 8051 architecture is used in control and interface functions for computer subsystems and peripherals, household appliances, data and communications equipment, and industrial control equipment. The microcontroller features 6 KB of flash memory to allow programming in three modes, in-system, in-application, or standard parallel programming.

Internal memory management logic enables application software to dynamically configure on-chip memory blocks by executing user software in one block while reprogramming the other. When that block is reprogrammed, software can switch the blocks so that the other can be erased and reprogrammed.

The flash memory boot loader supports in-system programming through the serial port, opening the entire flash memory to an external program source. For a third programming mode, the DS89C420 also supports standard flash memory or EPROM programmers.

Software written for 8051-based systems works with the DS89C420, except critical timing routines. The DS89C420 provides a stretch cycle feature and page or non-page memory interface modes to enable communication with slower external memory and peripherals.

Other features include two data pointers that can be used to move blocks of data both forward and backward and 13 interrupt sources with five priority levels. Three 16-bit timer/counters and a watchdog timer are included. An internal clock divider circuit provides a mode that enables the selection of processing speed based on software input and maintains all processes at lower power states without shutting down. A clock multiplier allows full-speed operation from lower speed, more readily available crystals.

The DS89C420 sells for $10.10 in quantities of 25,000.

Dallas Semiconductor
(972) 371-4448
www.dalsemi.com

02-01

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