T89C51CC01 Atmel, T89C51CC01 Datasheet - Page 96

• Manufacturer Part Number: T89C51CC01
• Description: Enhanced 8-Bit Microcontroller
• Manufacturer: Atmel

CAN Autobaud and
Listening Mode
Routines Examples
96
T89C51CC01
To activate the Autobaud feature, the AUTOBAUD bit in the CANGCON register must
be set. In this mode, the CAN controller is only listening to the line without acknowledg-
ing the received messages. It cannot send any message. The error flags are updated.
The bit timing can be adjusted until no error occurs (good configuration find).
In this mode, the error counters are frozen.
To go back to the standard mode, the AUTOBAUD bit must be cleared.
Figure 52. Autobaud Mode
1. Init of CAN macro
// Reset the CAN macro
// Disable CAN interrupts
// Init the Mailbox
{
}
// Configure the bit timing
CANGCON = 01h;
ECAN
ETIM
for num_page =0; num_page <15; num_page++
CANBT1 = xxh
CANBT2 = xxh
CANBT3 = xxh
CANPAGE = num_channel << 4;
CANCONCH = 00h
CANSTCH = 00h;
CANIDT1 = 00h;
CANIDT2 = 00h;
CANIDT3 = 00h;
CANIDT4 = 00h;
CANIDM1 = 00h;
CANIDM2 = 00h;
CANIDM3 = 00h;
CANIDM4 = 00h;
for num_data =0; num_data <8; num_data++)
CANGCON.3
AUTOBAUD
TxDC’
RxDC’
}
{
CANMSG = 00h;
= 0;
= 0;
1
0
4129K–CAN–01/05
TxDC
RxDC