DM8127 and Shared Memory

Hello,

Using IPNC_RDK v3.8.0 on DM8127 proprietary board.

I want to use shared memory between the ARM and the DSP.

In the \ipnc_rdk\ipnc_app\interface\inc\share_mem.h file there is a short example of how this is done.

The system itself has its own shared memory regions (in \ipnc_rdk\ipnc_app\interface\inc\Msg_Def.h) with their own "keys"

#define MSG_KEY			0x12345
#define SYS_MSG_KEY        0x36f9 ///< Message key used by system server.
#define FILE_MSG_KEY	0xc54be5 ///< File message key.
#define ALARM_KEY		0x542c7ae6 ///< Alarm message key.
#define AUD_MSG_KEY       0x31       ///< Audio alarm message key

If I init a new shared memory space for my own structure with a different key, how do I specify this new area in the following API functions?

void ShareMemRead(int offset,void *buf, int length); 
void ShareMemWrite(int offset,void *buf, int length);

Do I have to give a specific offset? How is it calculated?

I see that ShareMemInit uses all of the MAX shared memory.

int ShareMemInit(int key)
{
	mid = shmget(key, PROC_MEM_SIZE * MAX_SHARE_PROC, IPC_CREAT | 0660);
	if(mid < 0)
		mid = shmget(key, 0, 0);
	__D("shared memory id:%d\n",mid);
	if(mid < 0)
		return -1;
	return mid;
}

I also only found that the offset given for Shared memory is 

Thanks,

Mechi