Data Sheet

Table Of Contents

MCP2515

4.4.3 CONFIGURED AS DIGITAL OUTPUT

When used as digital outputs, the BFPCTRL.BxBFM bit

must be cleared and BFPCTRL.BnBFE must be set for

the associated buffer. In this mode, the state of the pin

is controlled by the BFPCTRL.BnBFS bits. Writing a ‘1’

to the BnBFS bit will cause a high level to be driven on

the associated buffer full pin, while a ‘0’ will cause the

pin to drive low. When using the pins in this mode, the

state of the pin should be modified only by using the Bit

Modify SPI command to prevent glitches from

occurring on either of the buffer full pins.

TABLE 4-1: CONFIGURING RXNBF PINS

FIGURE 4-2: RECEIVE BUFFER BLOCK DIAGRAM

BnBFE BnBFM BnBFS Pin Status

0XXDisabled, high-impedance

11XReceive buffer interrupt

100Digital output = 0

101Digital output = 1

Acceptance Mask

RXM1

Acceptance Filter

RXF2

Acceptance Filter

RXF3

Acceptance Filter

RXF4

Acceptance Filter

RXF5

Acceptance Mask

RXM0

Acceptance Filter

RXF0

Acceptance Filter

RXF1

Identifier

Data Field Data Field

Identifier

Note: Messages received in the MAB are intially

applied to the mask and filters of RXB0. In

addition, only one filter match occurs (e.g.,

if the message matches both RXF0 and

RXF2, the match will be for RXF0 and the

message will be moved into RXB0).