DS2406

OVERVIEW

The block diagram in Figure 1 shows the relationships between the major control and memory sections of

the DS2406. The device has four major data components: 64-bit lasered ROM, 1024 bits of EPROM data

memory, status memory, and the PIO-control block. The hierarchical structure of the 1-Wire protocol is

shown in Figure 2. The bus master must first provide one of the five ROM function commands: Read

ROM, Match ROM, Search ROM, Skip ROM, or Conditional Search ROM. The protocol required for

these ROM functions is described in Figure 13. After a ROM functions command is successfully

executed, the PIO-control and memory functions become accessible and the master may provide any one

of the six memory- and control function commands. The protocol for these functions is described in

Figure 7. All data is read and written least significant bit first.

HIERARCHICAL STRUCTURE FOR 1-Wire PROTOCOL Figure 2

DS2406

Command

Level

Available

Commands

Data Fields

Affected

1-Wire Bus

Other

Devices

Bus

Master

Read ROM

Match ROM

Search ROM

Skip ROM

Conditional

Search ROM

64-bit ROM

64-bit ROM

64-bit ROM

N/A

Conditional Search Settings

at Status Memory Location 7,

Write Memory

Write Status

Read Memory

Read Status

Ext. Read Memory

Channel Access

Status Memory

1024-bit EPROM

PIO Channels

1024-bit EPROM

Status Memory

1024-bit EPROM

DS2406 specific

Memory Function

Commands (see Figure 7)

1-Wire ROM Function

Commands (see Figure 13)

64-bit ROM,

Device/Channel Status

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