CAN MCP2515 Lib API

Applicable for

Colibri PXA270 | Colibri PXA300 | Colibri PXA310 | Colibri PXA320 | Colibri T20

Data Structures

struct tCanMessageExt

Macros
#define	STANDARD 0x00
	Use standard (11 bits ID) frame types. More...

#define	EXTENDED 0x01
	Use extended (29 bits ID) frame types. More...

#define	PXA_TYPE (0)
	PXA type. More...

#define	TEG_TYPE (1)
	Tegra type. More...

#define	UNKNOWN_TYPE (2)
	Unknown type. More...

#define	CAN_VER_MAJ 2
	Version info. More...

#define	CAN_VER_MIN 0

#define	CAN_VER_BUILD 0

#define	MSG_DATA_LENGTH (8)

Typedefs
typedef struct tCanMessageExt	canMessageExt

Functions
BOOL	CANLibMCP2515WriteDescriptor (DWORD device, DWORD description, DWORD mask)

INT32	CANLibMCP2515ReadDescriptor (DWORD device)

INT32	CANLibMCP2515ReadMask (DWORD device)

BOOL	CANLibMCP2515Reset (DWORD device)

BOOL	CANLibMCP2515SetBaudrate (DWORD device, DWORD baud)

BOOL	CANLibMCP2515TransmitMessage (DWORD device, canMessageExt *message, DWORD timeout)

DWORD	CANLibMCP2515ReceiveMessages (DWORD device, canMessageExt *message, DWORD numberOfMessages, DWORD timeout)

INT32	CANLibMCP2515Init (DWORD device, DWORD interruptGpio, DWORD waterMark, DWORD bufferSize, DWORD processorType)

void	CANLibMCP2515DeInit (DWORD device)

INT32	CANLibMCP2515GetStatus (DWORD device)

void	CANLibMCP2515PrintMessage (canMessageExt *message)

void	CANLibMCP2515GetLibVersion (DWORD verMaj, DWORD verMin, DWORD *buildNumber)

void	CANLibMCP2515ResetInterruptFlags (DWORD device)

void	DumpMcp2515 (DWORD device)

Detailed Description

Header for MCP2515 CAN controller library.

Copyright: Copyright (c) 2012 Toradex AG

Author: andy.kiser

Rev: 2863

Date: 2015-06-26 17:18:52 +0200 (Fr, 26 Jun 2015)

Target Platforms:: Colibri PXAxxx, T20

Macro Definition Documentation

#define CAN_VER_BUILD 0

#define CAN_VER_MAJ 2

Version info.

#define CAN_VER_MIN 0

#define EXTENDED 0x01

Use extended (29 bits ID) frame types.

#define MSG_DATA_LENGTH (8)

#define PXA_TYPE (0)

PXA type.

#define STANDARD 0x00

Use standard (11 bits ID) frame types.

#define TEG_TYPE (1)

Tegra type.

#define UNKNOWN_TYPE (2)

Unknown type.

Typedef Documentation

typedef struct tCanMessageExt canMessageExt

Structure for standard and extended frame types the size of this struct must be a multiple of 4!

Function Documentation

void CANLibMCP2515DeInit ( DWORD device )

Deinitializes MCP2515 controller and related functions

Parameters

[in] device Instance number (0..3)

void CANLibMCP2515GetLibVersion	(	DWORD *	verMaj,
		DWORD *	verMin,
		DWORD *	buildNumber
	)

Request Library Revision

Parameters

[out]	verMaj	Major library version
[out]	verMin	Minor library version
[out]	buildNumber	Library Build number

INT32 CANLibMCP2515GetStatus ( DWORD device )

Returns CAN status for the particular instance.
The error status is sticky. Once an error has occured, this function returns the error value, until it is cleared by calling either CANLibMCP2515Init() or CANLibMCP2515Reset().

Parameters

[in] device Instance number (0..3)

Return values

0	No Error CAN status information
0x20	The MCP2515 triggered an error interrupt (MCP_ERRIF \| MCP_WAKIF \| MCP_MERRF)

INT32 CANLibMCP2515Init	(	DWORD	device,
		DWORD	interruptGpio,
		DWORD	waterMark,
		DWORD	bufferSize,
		DWORD	processorType
	)

Initializes CAN Controller

Parameters

[in]	device	Instance number (0..3) The instance number defines the SPI channel used to communicate with the CAN controller: On Colibri PXA: 0->SPI1 1->SPI3 2->SPI2 3->SPI4 On Colibri T20: 0->SPI4 1->SPI3 2->SPI2 3->SPI4 On Colibri T30: 0->SPI1 1->SPI3 2->SPI2 3->SPI4 On Apalis T30: 0->SPI2 1->SPI4
[in]	interruptGpio	GPIO where the MCP2515's nINT signal is connected to.
[in]	waterMark	This parameter is not used anymore, the value ignored.
[in]	bufferSize	Number of CAN Messages the Receive Buffer can hold
[in]	processorType	This parameter is not used anymore, the value ignored.

Return values

0	Success
!=0	error. the value represents internal error codes

void CANLibMCP2515PrintMessage ( canMessageExt * message )

INT32 CANLibMCP2515ReadDescriptor ( DWORD device )

Reads acceptance code from the local shadow variable (no SPI communication).
This function was copied from the CAN SJA1000 implementation, but the feature is not available for the MCP2515.

Parameters

[in] device Instance number (0..3)

Return values

Acceptance code

INT32 CANLibMCP2515ReadMask ( DWORD device )

Reads the mask value from the local shadow variable (no SPI communication)

Parameters

[in] device Instance number (0..3)

Return values

Acceptance Mask

DWORD CANLibMCP2515ReceiveMessages	(	DWORD	device,
		canMessageExt *	message,
		DWORD	numberOfMessages,
		DWORD	timeout
	)

Receives CAN messages

Parameters

[in]	device	Instance number (0..3)
[out]	message	Aray of received CAN messages. See description of canMessageExt in canlib-MCP2515.h for details.
[in]	numberOfMessages	Number of messages to receive
[in]	timeout	Maximum time to wait for a Receive interrupt [ms] The time-out value needs to be a positive number between zero and 0x7FFFFFFF, or the infinite time-out value 0xFFFFFFFF

Return values

Number of Received Messages

BOOL CANLibMCP2515Reset ( DWORD device )

Clear local read and write message buffers and reset the MCP2515.

Parameters

[in] device Instance number (0..3)

Return values

TRUE Success

void CANLibMCP2515ResetInterruptFlags ( DWORD device )

BOOL CANLibMCP2515SetBaudrate	(	DWORD	device,
		DWORD	baud
	)

Set the CAN Baudrate and configure the MCP2515 mode to "Normal Operation"

Parameters

[in]	device	Instance number (0..3)
[in]	baud	New Baud Rate [kbps] Accepted values are: 1000, 800, 500, 250, 125, 100, 50, 20, 10

Return values

TRUE	Mode change successful
FALSE	Failure

BOOL CANLibMCP2515TransmitMessage	(	DWORD	device,
		canMessageExt *	message,
		DWORD	timeout
	)

Sends a CAN message

Parameters

[in]	device	Instance number (0..3)
[in]	message	CAN message to transmit. See description of canMessageExt in canlib-MCP2515.h for details.

Return values

TRUE	Success
FALSE	Failure

BOOL CANLibMCP2515WriteDescriptor	(	DWORD	device,
		DWORD	description,
		DWORD	mask
	)

Writes acceptance code and mask register. The mask register is also stored in a local shadow variable.

Parameters

[in]	device	Instance number (0..3)
[in]	description	New acceptance code(32bits). This parameter was copied from the CAN SJA1000 implementation, but the feature is not available for the MCP2515. It has no effect.
[in]	mask	New acceptance mask(32bits)

Return values

TRUE	Success
FALSE	Failed cases

void DumpMcp2515 ( DWORD device )

Outputs the regsister values

Parameters

[in] device Instance number

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