ISL40 Datasheet, PDF (4/12 Pages) Yamar Electronics Ltd. – Independent DC-LIN Slave For Asynchronous Communication Over Noisy Lines

Proprietary and Confidential Information of YAMAR Electronics Ltd.
Read-state:
Detecting Read-state header causes the ISL40 to send its input pins current state.
The Read-state message from the master consists of 3 bytes - sync break, sync field and identifier. The
identifier of this message begins with the four-bit ID of the device, 00, followed by the 2 protection bits.
The ISL40 responds with a data byte containing its eight input Signal pins followed by the checksum
byte. The checksum is the sum of the protected identifier and of the data byte as in LIN2.0.
Figure 3.2 shows a generic read state message.
Sync break
Sync Field
Master
P1, P0, 0, 0, Address
Data (8 input bits)
Checksum
Slave
Figure 3.2 Read State message
Read-change:
This header from the master causes the ISL40 to send information on changes of its input pins since
the last Read message. The first change on the pin after the Read message switches its sent value.
This command enables a detection of a pulse like change that accord between two consecutive Read
commands.
Figure 3.3 shows the process of determining the sent value of an input pin.
Sent value
Input pin level
Read message
1 bit
Figure 3.3 - Determining the recent changed value of an input pin
The Read-change message from the master has 3 bytes - sync break, sync field and identifier.
The identifier begins with the destination device four-bit ID, followed by 01 and terminating with 2
protection bits. The response for this Read-changes message is a data byte containing the ISL40`s
input pins recent changed value, followed by the checksum byte. The checksum is according to LIN2.0
specifications. Figure 3.4 shows a Read-changes message.
Sync break
Sync Field
Master
P1, P0, 1, 0, Address
Data (8 input bits)
Checksum
Slave
Figure 3.4 Read-changes message
Sleep message:
This type of message consist of 5 bytes - sync break, sync field, “3C” Hex, “00” Hex and checksum.
The sleep message identifier is “3C”Hex as in LIN2.0 specifications and the following data byte
“00”Hex.
Upon reception of sync break, sync field, “3C”Hex and “00”Hex bytes, the device enters sleep mode
immediately, therefore, as a result its following bytes and checksum are ignored.
© 2007 Yamar Electronics Ltd.
4
DS-ISL40 R1.6