Motorola MCF5281, MCF5282 FlexCAN Control Register 1 CANCTRL1, 11describes the CANCTRL1 fields

Models: MCF5282 MCF5281

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Programmer’s Model

 

 

 

Table 25-9. CANCTRL0 Field Descriptions

 

 

 

 

Bits

Name

 

Description

 

 

 

 

 

Bus off interrupt mask. The BOFF MASK bit provides a mask for the bus off interrupt.

7

BOFFMSK

0

Bus off interrupt disabled.

 

 

1

Bus off interrupt enabled.

 

 

 

 

 

Error interrupt mask. The ERRMSK bit provides a mask for the error interrupt.

6

ERRMSK

0

Error interrupt disabled.

 

 

1

Error interrupt enabled.

 

 

 

5–3

Reserved

 

 

 

 

 

Receive pin configuration control. This bit determines the polarity of the CANRX pin.

2

RXMODE

0

A logical ‘0’ is interpreted as a dominant bit; a logical ‘1’ is interpreted as a recessive bit.

 

 

1

A logical ‘1’ is interpreted as a dominant bit; a logical ‘0’ is interpreted as a recessive bit.

 

 

 

1–0

TXMODE

Transmit pin configuration control. This bit field controls the configuration of the CANTX pin. See

 

 

Table 25-10.

 

Table 25-10. Transmit Pin Configuration

 

 

TXMODE[1:0]

Transmit Pin Configuration

 

 

00

Full CMOS 1; positive polarity (CANTX= 0 is a dominant level)

01

Full CMOS1; negative polarity (CANTX = 1 is a dominant level)

1X

Open drain 2; positive polarity

1Full CMOS drive indicates that both dominant and recessive levels are driven by the chip.

2Open drain drive indicates that only a dominant level is driven by the chip. During a recessive level, the CANTX pin is disabled (three stated), and the electrical level is achieved by external pull-up/pull-down devices. The assertion of both Tx mode bits causes the polarity inversion to be cancelled (open drain mode forces the polarity to be positive).

25.5.3FlexCAN Control Register 1 (CANCTRL1)

7

6

5

4

3

2

1

0

Field

SAMP

TSYNC

LBUF

 

LOM

 

PROPSEG

 

 

 

 

 

 

 

 

 

 

Reset

 

 

 

0000_0000

 

 

 

 

 

 

 

 

 

 

 

 

R/W

 

 

 

 

R/W

 

 

 

 

 

 

 

 

 

 

 

Address

 

 

 

IPSBAR + 0x1C_0007

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 25-8. FlexCAN Control Register 1 (CANCTRL1)

Table 25-11describes the CANCTRL1 fields.

MOTOROLA

Chapter 25. FlexCAN

25-23

Page 549
Image 549
Motorola MCF5281 FlexCAN Control Register 1 CANCTRL1, 11describes the CANCTRL1 fields, CANCTRL0 Field Descriptions