Preliminary and proprietary Information of YAMAR Electronics Ltd. Subject to change without notice.

© 2010 Yamar Electronics Ltd.

8

DS-SIG61 R0.932

4

DEVICE OPERATION

The following paragraph describes the operation of the SIG61 device.

4.1

Protocol

The device operation is controlled via 5 types of commands:

Write command - Upon receiving a Write command with the SIG61 specific ID, the device shall output

the data byte content as indicated by the command to its Output pins.

Read command - Upon receiving a Read massage with the SIG61 specific ID, the device shall

respond by sending a message containing the status of its Input pins (followed by an appropriate

checksum).

Read-Change command - When receiving a Read-Change massage with the SIG61 specific ID, the

device shall respond to the command by indicating if a pulse upon detecting the first change on its input

pins. The response message shall contain the new status of the input pins followed by an appropriate

checksum.

Sleep command - Upon receiving a Sleep command, the device shall enter a low power-consumption

(sleep) mode. A wakeup message generated by the master, or by any of the slaves, wakes up all the

devices on the network. This is a global message targeting all the slaves in the network.

Change-Frequency command - Upon receiving Change-Frequency command, the device shall switch

from its current operational frequency to the other. This command is a global command targeting all the

slaves in the network.

4.1.1

Command structure

The structure of the five types of commands is detailed below.

Command type 1: Write command.

The Write command consists of 5 bytes: sync break, sync field, Identifier, data and checksum.

The identifier byte begins with the device four ID bits, followed by 00 bits and 2 protection bits.

Upon receiving a write command, if checksum and protection bits calculations are successful, the data

byte content is transferred to the corresponding output pins.

Sync break:

Sync break length is at least 13 bit times with compliance to Lin protocol.

Protection bits calculation:

P0 =

(Identifier [0]) XOR (Identifier [1]) XOR (Identifier [2]) XOR (Identifier [4])

P1 = ~ ((Identifier [1]) XOR (Identifier [3]) XOR (Identifier [4]) XOR (Identifier [5]))

Checksum calculation:

The checksum is an inverted 8 bit sum of the Identifier and Data byte including (own) carry:

Checksum = ~ ( Identifier Byte + Data Byte + Carry)