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2.2

ADR 1: CTCR CAN-Transceiver Control Register

Figure 12.

Three basic operating modes are available using different logic combinations on ACT and TXEN. Each of these

modes in conjunction with other inputs has its unique combination of parameters inside the specification:

Table 6.

Operating Modes of the CAN Lineinterface

Input Signals

Output Signals

ACT

TXEN

TX

CANH

CANL

V3

Mode

RTL

RTH

CANH

CANL

RX

0

X

X

RTH

RTL

ON

Standby

GND

OFF

OFF

1

1

0

1/0

RTH

RTL

ON

RXonly

GND

OFF

OFF

TX

1

0

1

RTL

ON

RXonly

GND

OFF

OFF

1

0

1

RTH

ON

RXonly

GND

OFF

OFF

1

1

1

RTH

RTL

ON

Normal

GND

ON

ON

1

1

1

0

RTH

RTL

ON

Normal

GND

VDD

GND

0

1

1

1

RTL

ON

Normal

GND

ON

ON

1

1

1

RTH

ON

Normal

GND

ON

ON

11

RTH

RTL

ON

Error X

GND

OFF

OFF

1

1X

1

RTL

ON

Error

VII, VIII

ISRC

OFF

ON

CANL

1X

1

RTL

ON

Error

EIII, VII, VIII

ISRC

OFF

ON

CANL

1

X

1

GND

x 3

ON

Error

EI_V

GND

ON

ON

1X

1

x 3

ON

Error

EII_IX

GND

ON

ON

1X

1

RTH

ON

Error

EVI

ISRC

GND

ON

OFF

CANH

1X

1

RTH

ON

Error

EVII, EIV

ISRC

GND

ON

OFF

CANH

1X

1

ON

Error

EVII

ISRC

GND

ON

OFF

CANH

RES

TXEN

ACT

RES

RES

LP2

Reserved bits (‘RES’) have to be written as ‘0’.

CAN-Transceiver application control

0X : Standby / Sleep

10 : Receive only mode A (Readback TX, if not EX)

11 : Normal Operation

D7

D0

Note, that TXEN is automatically reset upon

occurence of EX (TX permanent dominant)

and has to be reprogrammed after problem

correction to enter normal mode.

LP1

LP0

Standby-mode control (V1 only, see 1.1)

enable Auto-Osc-Off

reduce Osc-frequency to 250KHz