Basic CAN Project 1.4

Purpose

This project uses the Controller Area Network (CAN).

Description

Upon startup, the program will configure the CAN, and make synchronization. If connected to other board, user can send a frame by pressing a key.

The basic will :

• CAN0 Mailbox 1, transmit, with acceptance mask
• CAN0 Mailbox 2, transmit, no acceptance mask
• Dump registers (for debug purpose)

Usage

1. Build the program and download it inside the evaluation board. Please refer to the SAM-BA User Guide, the GNU-Based Software Development application note or to the IAR EWARM User Guide, depending on your chosen solution.
2. On the computer, open the DBGU port with a terminal application (e.g. HyperTerminal on Microsoft Windows).
• Settings: 115200 bauds, 8 bits, 1 stop bit, no parity, no flow control.
3. If you have 2 boards:
• Connect the CAN D+ board 1 to the CAN D+ board 2, and then CAN D- board 1 to the CAN D- board 2.
• Run the software on the 2 boards. You should get the following traces:

  BOARD 1: (we press the key 1)
-- Basic CAN Project 1.4 --
-- AT91SAM7X-EK
IP version: 0x121
CAN_Synchronisation
-I- CAN0 Initialisations Completed
INIT OK
CAN0 Mailbox 1, transmit, with acceptance mask

BOARD 2:
-- Basic CAN Project 1.4 --
-- AT91SAM7X-EK
IP version: 0x121
CAN_Synchronisation
-I- CAN0 Initialisations Completed
INIT OK
Press a Key [1:transmit 2:transmit 3:dump register]
Receive Maibox Number: 5
Read data low 0xAABBCCDD
Read data high 0x11223344
CAN0 Mailbox 1, transmit, with acceptance mask
Dump registers
CAN_MR: 0x1
CAN_IMR: 0x1F0000FF
CAN_SR: 0x610000
CAN_BR: 0x23534
CAN_ECR: 0x0
CAN_MB_MMR: 0x1000000
CAN_MB_MAM: 0x20080000
CAN_MB_MID: 0x80000
CAN_MB_MSR: 0x0
CAN_MB_MDL: 0x0
CAN_MB_MDH: 0x0


4. With the AT91SAM7A3:
• The AT91SAM7A3 has 2 can on its board. For the test, no need of 2 boards. Only connect CAN1 D+ to CAN2 D+ and CAN1 D- ton CAN2 D+.
• Launch the software. The software make a test of the 2 can. You should get the following output on the DBGU:

  -- Basic CAN Project 1.4 --
-- AT91SAM7A3-EK
IP version: 0x121
CAN_Synchronisation
-I- CAN0 Initialisations Completed
-I- CAN1 Initialisations Completed
With Interrupt CAN0 Mailbox 0 transmitting to CAN1 Mailbox 0
Test passed
With Interrupt CAN0 Mailboxes 1 & 2 transmitting to CAN1 Mailbox 15
Test passed
With Interrupt CAN0 Mailboxes 1 & 2 transmitting to CAN1 Mailbox 15
Wait, wait, wait, wait
Test passed
With Interrupt CAN0 Mailbox 3 asking for CAN1 Mailbox 3 transmission
Test passed
Without Interrupt CAN0 Mailbox 0 transmitting to CAN1 Mailbox 0
Test passed
Without Interrupt CAN0 Mailboxes 1 & 2 transmitting to CAN1 Mailbox 15
Test passed
Without Interrupt CAN0 Mailboxes 1 & 2 transmitting to CAN1 Mailbox 15
Test passed
Without Interrupt CAN0 Mailbox 3 asking for CAN1 Mailbox 3 transmission
Test passed


Atmel Corporation ©2008