Intel 87C196CB Can Controller Signals And Registers, Can Serial Communications Controller

Models: 8XC196NT 87C196CB

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7.2CAN CONTROLLER SIGNALS AND REGISTERS

CAN SERIAL COMMUNICATIONS CONTROLLER

7.2CAN CONTROLLER SIGNALS AND REGISTERS

Table 7-1 describes the CAN controller’s pins, and Table 7-2 describes the control and status reg- isters.

 

 

Table 7-1. CAN Controller Signals

Signal

Type

Description

 

 

 

RXCAN

I

Receive

 

 

This signal carries messages from other nodes on the CAN bus to the CAN controller.

 

 

 

TXCAN

O

Transmit

 

 

This signal carries messages from the CAN controller to other nodes on the CAN bus.

 

 

 

Table 7-2. Control and Status Registers

Register

Register

Description

Mnemonic ††

Address ††

 

 

 

CAN_BTIME0

1E3FH

Bit Timing 0

 

 

Program this register to define the length of one time quantum

 

 

and the maximum number of time quanta by which a bit time can

 

 

be modified for resynchronization.

 

 

 

CAN_BTIME1

1E4FH

Bit Timing 1

 

 

Program this register to define the sample time and mode.

 

 

 

CAN_CON

1E00H

Control

 

 

Program this register to prevent transfers to and from the CAN

 

 

bus, to enable and disable CAN interrupts, and to control write

 

 

access to the bit timing registers.

 

 

 

CAN_EGMSK

1E08H, 1E09H,

Extended Global Mask

 

1E0AH, 1E0BH

Program this register to mask (“don’t care”) specific message

 

 

 

 

identifier bits for extended message objects.

 

 

 

CAN_INT

1E5FH

CAN Interrupt Pending

 

 

This read-only register indicates the source of the highest-priority

 

 

pending interrupt.

 

 

 

CAN_MSGxCFG

1Ey6H

Message Object x Configuration

 

 

Program this register to specify a message object’s data length,

 

 

transfer direction, and identifier type.

 

 

 

CAN_MSGxCON0

1Ey0H

Message Object x Control 0

 

 

Program this register to enable or disable the message object’s

 

 

successful transmission (TX) and reception (RX) interrupts. Read

 

 

this register to determine whether a message object is ready to

 

 

transmit and whether an interrupt is pending.

 

 

 

The CCE bit in CAN_CON must be set to enable write access to the bit timing registers. †† In register names, x = 1–15; in addresses, y = 1–F.

7-3

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Intel 87C196CB Can Controller Signals And Registers, Can Serial Communications Controller, 1. CAN Controller Signals