View ds2404s datasheet:

DS2404S-C01 Dual Port Memory Plus Time www.dalsemi.com FEATURES PIN ASSIGNMENT Bridge for electronic equipment to the 1- Wire MicroLAN 4096 bits of nonvolatile dual-port memory VCC 116 VCC including real time clock/calendar in binary IRQ 215 X1 format, programmable interval timer, and RST 314 X2 programmable power-on cycle counter 1-Wire interface for MicroLAN DQ 413 GND communication at 16.3k bits per second I/O 512 NC 3-Wire host interface for high-speed data CLK 611 1HZ communications at 2M bits per second NC 710 VBATO Unique, factory-lasered and tested 64-bit GND 8 9 VBATB registration number (8-bit family code + 48- bit serial number + 8–bit CRC tester) assures 16-PIN SOIC (300 MIL) absolute traceability because no two parts are See Mech. Drawings Sectio