求教，用c语言基于VISA驱动，实现安捷伦和usb设备通讯采集数据

delylin 2016-05-16 08:28:15

用c语言编写采集软件基于VISA驱动，实现和usb设备通讯采集数据的功能。
问题来源：之前用的是安捷伦34970a采集数据，C++编写的采集软件，采用安捷伦提供的rs232通讯接口代码，可以正常采集数据；由于设备更新换成安捷伦34792a的采集仪，坑爹的没有rs232通讯功能，只有报警功能，只能使用usb和电脑连接，需要修改代码，求高手帮忙？问了好多人，都不了解visa。
我就贴出一段安捷伦提供的rs232 的open_port这段代码，全码我放网盘里地址：http://pan.baidu.com/s/1miguXOs
USB的地址：USB0::0x3923::0x12C0::00B50DAE::INSTR

 void open_port()

//************************************************************************************

// This function opens a port (the communication between the instrument and computer). 

// Be sure that the GPIB address has been set in the 'GPIBAddr' variable before 

// calling this routine.

//************************************************************************************

{

	long	start,finish;

	char	ch;



	// Open the Visa session

	errorStatus = viOpenDefaultRM(&videfaultRM);



	// Open communication to the instrument

	errorStatus = viOpen(videfaultRM, "ASRL1::INSTR", VI_TRUE, VI_TRUE, &vi);

	// If an error occurs, give a message

	if (errorStatus < VI_SUCCESS)

	{

		printf("Unable to Open port; check address.\nPress any key to exit.");

		scanf("%c", &ch);

		exit(1);

	}



	// Set the RS-232 parameters; refer to the 34970A and VISA documentation

	// to change the settings. Make sure the instrument and the following

	// settings agree.

	errorStatus = viSetAttribute(vi, VI_ATTR_ASRL_BAUD, 115200);

	errorStatus = viSetAttribute(vi, VI_ATTR_ASRL_DATA_BITS, 8);

	errorStatus = viSetAttribute(vi, VI_ATTR_ASRL_PARITY, VI_ASRL_PAR_NONE);

	errorStatus = viSetAttribute(vi, VI_ATTR_ASRL_STOP_BITS, VI_ASRL_STOP_ONE);

	errorStatus = viSetAttribute(vi, VI_ATTR_ASRL_FLOW_CNTRL, VI_ASRL_FLOW_XON_XOFF);



	// Set the instrument to remote

	send_cmd ("SYSTem:REMote");



	// Wait 1 second

	time(&start);

	finish=start + 1;

	do

	{

		time(&start);

	} while (start < finish); 



}