E520.14 Datasheet, PDF (36/41 Pages) ELMOS Semiconductor AG – Provides four HS-CAN physical interfaces

Quad CAN transceiver
PRODUCTION DATA – FEB 4, 2014
E520.14
4.6 SPI communication; pins SCK, SDI, SDO, CSN
The SPI interface is used for:
• storing-/and reading CAN data-/timing and system configurations
• reading diagnosis register
By setting CSN to low level, the communication can be achieved and by setting to high level leads to disabling the
communication (in this case, pin SDO is high impedance). During the transmission data shifts are controlled by the
serial clock signal (SCK) according to the following rules:
• data is shifted MSB first, LSB last
• data is shifted out on the rising edge of SCK and is sampled on the falling edge of SCK
• data transmission length is always 16 Bit
SPI write is performed setting MSB Bit A7 of address value to 1. During read Bit A7 needs to be 0.
Reading first byte of every SPI access provides status information, e.g. undervoltages, CAN status, CAN failures,
over temperature, wake ups or state.
Reading second byte of a SPI read access provides information of the register regarding to the given addresse.
Reading second byte of a SPI write access reflects first written byte, e.g bits RW..A0.
Register Name
STAT BYTE
Address
-
Description
Short overview of device status. Access with first byte at SDO with every SPI
access.
Table 36: RegisterTable
Register STAT BYTE (-)
MSB
Content
STATE OT
WAKE
SUPPLY CAN_ALL CAN_GT_ -
0
Reset value
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
Bit Description
STATE :
1..State ACTIVE
0..States SLEEP or STANDBY
OT :
1..Over temperature was detected
0..Over temperature was not detected
WAKE :
1..Wake up conditions were detected
0..Wake up condition was not detected
SUPPLY :
1..Undervoltage conditions at VCC, VIO or VS were detected
0..Undervoltage condition at VCC, VIO or VS was not detected
CAN_ALL :
1..All CANs are set to NORMAL operation
0..At least one CAN is not set to NORMAL operation
CAN_GT_0 :
1..At least one CAN is set to NORMAL operation
0..No CAN is set to NORMAL operation
CAN_ERROR :
1..CAN failure condition in any CAN detected
0..CAN failure condition any CAN not detected
LSB
CAN_ERR
OR
0
R
Table 37: Short overview of device status. Access with first byte at SDO with every SPI access.
Elmos Semiconductor AG reserves the right to change the detail specifications as may be required to permit improvements in the design of its products.
Elmos Semiconductor AG
Data Sheet 36 / 41
QM-No.: 25DS2014E.02