/*********************************************************
* This code is designed to run in CVI.  It               *
* demonstrates low level VXI functions by doing the      *
* following calls to read the configuration registers    *
* from logical address 0.  Flow of code is:              *
* 														 *
* 1)  VXIinReg() to read the offset specified by user.   *
* 2)  VXIin() to read same register as VXIinReg()        *
* 3)  VXImove() to read all 4 read-able config registers *
*********************************************************/

#include <nivxi.h>
#include <utility.h>
#include <ansi_c.h>

static char ch;
static int regstr, offset, width;
static UINT32 address, length, dstaddr, srcaddr;
static NIVXI_STATUS Status;
static UINT16 value, reg, dstparms, srcparms, accessparms, move_buffer[4];
static INT16 la;

void main ()
{
	if ( InitVXIlibrary() )	//This function must be called to use VXI functions.
	{
		printf ("Unable to Initialize VXI library... exiting");
		exit (0);
	}
	
	Cls();
	
    /*
	 * First we need to find out what offset the user wants.  We will
	 * store this choice in "offset".
	 */
	 printf ("What configuration register would you like to read? (0-3) >> ");
	 scanf ("%d",&regstr);
	 offset = 2 * regstr;
	 
	/*
	 * also need to find out what LA the user wants to read from
	 */
	 printf ("What logical address should I read from? >> ");
	 scanf ("%d", &la);

	/* 
	 * Next do VXIinReg().  Parameters are as follows:
	 *
	 * la:              logical address of device we want to read from.
	 * reg:             configuration register we want to read.
	 * value:           data read from operation.
	 */
	reg = offset;		   //offset was set by user.  Notice that
	                       //this is **NOT** the ABSOLUTE address in A16.
	Status = VXIinReg (la, reg, &value);
		
		if (Status)		       
		{		// An error occurred
			printf ("Error in VXIinReg.  Status = %d\n", Status);
		}
		else	//transfer successful, so print result to user.
		{
			printf ("Value from VXIinReg = 0x%x\n", value);
		}
		
	/* Now do the same operation by using VXIin().  parameters are:
	 * 
	 * accessparms:   access priviledges, address space, etc.
	 * address:       absolute address within A16, A24, or A32 space.
	 * width:         1=byte, 2=word, 3=long word.
	 * value:         data resulting from operation.   
	 */
    accessparms = 0x1;          //A16, non-privilidged data
    address = 0xC000 + offset;  //absolute address to read
    width = 2;                  //read a word
	Status = VXIin (accessparms, address, width, &value);

		if (Status)
		{       // An error occurred
			printf ("Error in VXIin.  Status = %d\n", Status);	
		}
		else
		{
	       	printf ("Value from VXIin = 0x%x\n", value);
	    }
	       	
	/*
	 * Now do VXImove.  Parameters are as follow:
	 *
	 * srcparms: which address space to use as the source of 
	 *             the move operation.
	 * srcaddr:  address offset within the source address space.
	 * dstparms: address space to use as the  destination 
	 *             of the move operation.
	 * dstaddr:  address offset within the destination address space.
	 * length:   number of elements to move.
	 * width:    size of each element to move.
	 */
	srcparms = 0x1;        //source is A16 space.
	srcaddr = 0xC000;      //begin move at A16 address 0xC000.
	dstparms = 0x0;        //destination is a local buffer.
	length = 4;            //move 4 elements.
	width = 2;			   //move each element as a word. 
	dstaddr = (UINT32)move_buffer;	 //typecast pointer to UINT32 to
	                                 //pass array beginning address.
	Status = VXImove (srcparms, srcaddr, dstparms, dstaddr,
					  length, width);
		if (Status)
		{		// An error occurred
			printf ("Error in VXImove.  Status = %d\n", Status);	
		}
		else
		{		//VXImove was successful, print results
			printf ("\nData from VXImove follows:\n");
			printf ("Register 0 = 0x%x\n", move_buffer[0]);
			printf ("Register 1 = 0x%x\n", move_buffer[1]);
			printf ("Register 2 = 0x%x\n", move_buffer[2]);
			printf ("Register 3 = 0x%x\n", move_buffer[3]);
		}
	
	printf ("<Press any key to quit>");
	getchar ();
	scanf ("%c", &ch);   //wait for user to hit a key to quit
	
	CloseVXIlibrary();   //close VXI library.
}