DS1996

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1-WIRE SIGNALING

The DS1996 requires strict protocols to ensure data integrity. The protocol consists of four types of

signaling on one line: Reset Sequence with Reset Pulse and Presence Pulse, Write 0, Write 1 and Read

Data. All these signals except presence pulse are initiated by the bus master. The DS1996 can

communicate at two different speeds, regular speed and Overdrive speed. If not explicitly set into the

overdrive mode, the DS1996 will communicate at regular speed. While in Overdrive Mode the fast timing

applies to all wave forms.

The initialization sequence required to begin any communication with the DS1996 is shown in Figure 10.

A reset pulse followed by a presence pulse indicates the DS1996 is ready to send or receive data given the

correct ROM command and memory function command. The bus master transmits (TX) a reset pulse

line and goes into receive mode (RX). The 1-Wire bus is pulled to a high state via the pullup resistor.

Overdrive speed).

A Reset Pulse of 480 µs or longer will exit the Overdrive Mode returning the device to regular speed. If

the DS1996 is in Overdrive Mode and the Reset Pulse is no longer than 80 µs the device will remain in

Overdrive Mode.