CiA 401 CoIDE example
============================

This is an example application implementing a CANopen CiA 401 device on
the STM32F4 Discovery Board.
http://www.st.com/stm32f4-discovery
http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/LN1848/PF252419

The Discovery board itself does not have a CAN transceiver. To extend
it with a CAN transceiver and with a possibility to extend the
process IO capabilities and also the possibility to use printf() to watch
informal and debug messages, the STM32F4 Discovery Shield is used.
http://www.mikroe.com/stm32/stm32f4-discovery-shield/

The CANopen material, including the 401 code, is delivered as a pre-compiled
library libCANopenlib401.a.  The library is compiled using the same
definitions as the application in gen_define.h If you like to
extend the application example the restrictions have to be considered.
For example:
#define CO_NODE_ID	32		 only this fixed Node Id can be used
/* Definition of numbers of CANopen services */
#define CO_SDO_SERVER_CNT	1u
#define CO_PDO_TRANSMIT_CNT	2u
#define CO_PDO_RECEIVE_CNT	6u

Another restriction is the run time for the use of the CANopen code.
It runs little longer than one hour. Some Minutes before stopping,
exactly one hour after starting the example, the blue LED on the Discovery
board will signal the coming shut down.

The object dictionary itself and derived EDS file were generated using the
CANopen Device Designer
http://www.emtas.de/produkte/canopen-device-designer?lang=en
The object dictionary provides enough entries for extending the existing code
with process IO code. There is no need to extend it whether direct by changing
gen_objdict.c nor by using the Device Designer. 

The application code is completely visible in the example sources.
To handle process inputs and outputs there exist only 4 functions coded in
usr_401.c

- setting digital out ports as byte 
- reading digital in ports as byte
- writing to analog out converters as 16 bit value
- reading from analog digital converters as 16 bit values


The function used of the example to set digital outputs is 
void byte_out_printfInd(
        UNSIGNED8 port,         /**< selected 8bit port */
        UNSIGNED16 outVal       /**< output value */
    )
{
    printf("digout port:%2d, value:0x%02x, %3d\n",
            port, outVal, outVal);
}

and currently outputs the parameters given to the printf() function.
The result can be watched if a terminal is connected (1152008N1)
to USART2.  If the STM32F4 Discovery Shield is extended with one of
the Click boards available like "RELAY click" or the "8x8 B click",
the byte_out() function can be easily adopted to control these interfaces.

The name of the appropriate function used by the CiA401 profile is made
known by the event register function coEventRegister_401() in main.c :

  coEventRegister_401(
                byte_in_piInd,       /* digital in  HW API function   */
                byte_out_printfInd,  /* digital out HW API function   */
                analog_in_piInd,     /* the analog in HW API function */
                analog_out_printfInd /* analog out HW API function    */
                )

There are much more so-called indication functions registered to the
CANopen stack.  All of them are coded in main.c as well.  Mostly they
are doing nothing than signalling that they are called by sending some
text via printf(). As an example, every time the node's network status is
changed by a CANopen NMT master the stack calls the registered indication function 

RET_T nmtInd(
    BOOL_T  execute,
    CO_NMT_STATE_T  newState
)
{
	printf("USR: nmtInd: New Nmt state %d - execute %d\n", newState, execute);
	return(RET_OK);
}

We hope to have provided an easy to use and easy to understand example
on how to use the CANopen protocol stack.  The manuals are available via request
to service@emtas.de.  Please let us know when you are facing problems. 

Have fun extending the example.

emtas GmbH
http://www.emtas.de