T89C51CC01CA-7CTIM Atmel, T89C51CC01CA-7CTIM Datasheet - Page 82

• Manufacturer Part Number: T89C51CC01CA-7CTIM
• Description: IC 8051 MCU FLASH 32K 64BGA
• Manufacturer: Atmel
• Series: AT89C CANr

Specifications of T89C51CC01CA-7CTIM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: CAN, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-BGA
• For Use With: AT89STK-06 - KIT DEMOBOARD 8051 MCU W/CAN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: T89C51CC01CA7CTIM

Working on Message Objects
CAN Controller
Management
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A/T89C51CC01
The Page message object register (CANPAGE) is used to select one of the 15 message
objects. Then, message object Control (CANCONCH) and message object Status
(CANSTCH) are available for this selected message object number in the corresponding
SFRs. A single register (CANMSG) is used for the message. The mailbox pointer is
managed by the Page message object register with an auto-incrementation at the end of
each access. The range of this counter is 8.
Note that the maibox is a pure RAM, dedicated to one message object, without overlap.
In most cases, it is not necessary to transfer the received message into the standard
memory. The message to be transmitted can be built directly in the maibox. Most calcu-
lations or tests can be executed in the mailbox area which provide quicker access.
In order to enable the CAN Controller correctly the following registers have to be
initialized:
•
•
•
During operation, the CAN Enable message object registers 1 and 2 (CANEN 1 and 2)
gives a fast overview of the message objects availability.
The CAN messages can be handled by interrupt or polling modes.
A message object can be configured as follows:
•
•
•
•
This configuration is made in the CONCH field of the CANCONCH register (see
Table 56).
When a message object is configured, the corresponding ENCH bit of CANEN 1 and 2
register is set.
Table 56. Configuration for CONCH1:2
When a Transmitter or Receiver action of a message object is completed, the corre-
sponding ENCH bit of the CANEN 1 and 2 register is cleared. In order to re-enable the
message object, it is necessary to re-write the configuration in CANCONCH register.
Non-consecutive message objects can be used for all three types of message objects
(Transmitter, Receiver and Receiver buffer),
CONCH 1
General Control (CANGCON),
Bit Timing (CANBT 1, 2 and 3),
And for each page of 15 message objects
–
–
Transmit message object,
Receive message object,
Receive buffer message object.
Disable
0
0
1
1
message object Control (CANCONCH),
message object Status (CANSTCH).
CONCH 2
0
1
0
1
Type of Message Object
disable
Transmitter
Receiver
Receiver buffer
4129N–CAN–03/08