DALLAS SEMICONDUCTOR DSS001FP DS5001FP 128K Soft Microprocessor Chip FEATURES @ 8051 compatible microprocessor adapts to its task Accesses upto 128K bytes of nonvolatile SRAM In-system programming via on-chip serial port ~ Can modify its own program or data memory ~ Accesses memory on a separate Bytewide bus ~ Performs CRC-16 check of NV RAM memory ~ Decodes memory and peripheral chip enables * Crashproof Operation ~ Maintains all nonvolatile resources for over 10 years Power-fail Reset Early Warning Powerfail interrupt ~ Watchdog Timer Lithium backs user SRAM for program/data storage - Precision band-gap reference for power monitor @ Fully 8051 Compatible ~- 128K bytes scratchpad RAM ~ Two timer/counters ~ On-chip serial port ~ 32 paraliel /O port pins * Software Security Availabie with DS5002FP Secure Microprocessor DESCRIPTION The DS5001FP is an 8051 compatible microprocessor based on nonvolatile RAM technology. itis designed for systems that need large quantities of nonvolatile memory. Like its predecessor the DS5000(7), the DSS001FP is substantially more flexible than a stan- dard 8051. It provides full compatibility with the 8051 instruction set, timers, serial port, and parallel I/O ports. By using NV RAM instead of ROM, the user can pro- PIN ASSIGNMENT PO.4/AD4 2614 CE2 63 CES PE2 62 CE4 BAO 61 BD3 PO.3/AD3 60 P2.5/A13 BAS 59 Bb2 PO.2AD2 58 P2.4/A12 BAI3 57 BDI PUA I 3 P23iAul RAW 85 BDO Pd.0/ADO DSS001FP 5a Vu voce 3 BAI5 VCC GND MSEL Co | P2.2/A10 PLC } P2.VAS Bai4Cl P2.0/A8 Pit 48 (J XTALt BAI2 a7 EE XTALS P12 46 3 Ps 7/AD Bar 45 P3.6/HR 32 44 P35Tt PE3Cmo} 2 43 77 PF PE4 42 = VAST Bact 41 [II 3 470 a4 1 A. 25 26 27 28 29 30 31 32.33 34 35 36 3? 38.99 40_/ c=] BAO P14 BAS PIS BA4 P16 BAS PL? P3.1/TXD P3.2ANTO P3.3/INTI PROG BA2 RST BAI P3.0/RXD gram, then reprogram the microprocessor while insys- tem. The application software can even change its own operation. This allows frequent software upgrades, adaptive programs, customized systems, etc. In addi- tion, by using NV SRAM, the DS5001 FP is ideal for data logging applications. It also connects easily to a Dallas Real Time Clock for time stamp and date. 268