通过VISA库实现GPIB通信

一段VC写的VISA GPIB控制代码
注意事项：
1、必须先安装Agilent IO Library驱动，本人添加的是默认位置的库；装了驱动后有很多很好的文档 C:\Programm Files\Agilent\IO Libraries Suite\Manuals\visa.pdf
2、安捷伦提供SICL和VISA两种库，不推荐使用SICL，因为VISA更通用。NI也用VISA，函数名一致，都是viOpenDefaultRM,viOpen,viPrintf,viQueryf,viClose
3、GPIB是用来控制电子仪器的，主要用在自动化控制，测试上。标准是SCPI。
4、其实不难，但要多实践，指示调用APD（头文件visa.h，库agvisa32.lib），APD常用的就是几个，viOpenDefaultRM,viOpen,viPrintf,viQueryf,viClose...还有viSetAttribute,viScanf等；
viSetAttribute(vi,VI_ATTR_TMO_VALUE,20000); //超时时间s
其他的主要是SCPI命令，大多是标准化的，查查编程文档即可
5、较新的技术是：LXI（LAN Extention Interface），网口控制。因为一方面是GPIB接口较贵（3k-5k），设备也只能接十几个（通常足够了）；
6、扫描时需要单次同步，这样才准确
7、应该多在Agilent和NI官网看看
8、好书：《NI-VISA Programmers Man》,《Agilent VISA User's Guide》
9、自动搜索仪器，根据*IDN知道什么仪器
ViChar buffer[255];
ViRsrc mathes=buffer;
ViUInt32 nmatched;
ViFindList list;


viFindRsrc(defaultRM,"GPIB?*INSTR",&list,&nmatched,matched);
viFindNext(list,matches);
viFindNext(list,matches);
...
viClose(list);
10、 测量多个数据可能用到strtok函数,或直接保存到一个数组里；    
11、至于GPIB规范，总线电缆包括根信号线和根地线。根信号线中，根为数据线，根 为接口管理线，根为握手线。IFC，ATN，了解即可。 
12、FORMAT ASCii | In  自动校准用，写多了也没什么意思了。


信号源? 
//信号源设置较少，主要设置频率和功率。?
viPrintf(vi_sig,?"FREQ?999MHz\n");?
viPrintf(vi_sig,?"POW??0dBm\n");? 
viPrintf(vi_sig,?"OUTP?ON\n");?//射频开


viPrintf(vi_sig,?"MOD??ON\n");?//调制开?其他滤波器什么的，很少用。? 
最新的仪器有有个很强大的功能，按下某个键即可显示其相应的SCPI命令，?于此我们不用查编程文档了，真是爽歪歪。?
viPrintf(vi_sig,"DM:IQ:STATE?ON\n");? 
//?viPrintf(vi_4438c,?"OUTP:MOD:STAT?OFF\n");//?
//?viPrintf(vi_4438c,"DM:STATE?ON\n");


//频谱仪? 
viPrintf(vi_spec,?"SYST:DISP:UPDate?ON\n");? 
viPrintf(vi_spec,?"FREQ:CENT?%dMHz\n",m_cent_freq);?
viPrintf(vi_spec,?"FREQ:SPAN?%dMHz\n",m_span);? 
viPrintf(vi_spec,?"DISP:WIND:TRAC:Y:RLEV?%ddBm\n",m_rlevel);?
viPrintf(vi_spec,?"BAND:VID?%dkHz\n",m_rbw);?
viPrintf(vi_spec,?"BAND:RES?%dkHz\n",m_vbw);?
viPrintf(vi_spec,?"CALC:MARK:AOFF\n");


//////////////////////////////////////?
char?buf[255];? viPrintf(vi_spec,"INIT:CONT?OFF\n");?
viPrintf(vi_spec,"INIT:IMM;*WAI\n");?
viPrintf(vi_spec,"CALC:MARK:MAX\n");?
viPrintf(vi_spec,"*WAI\n");? 
viQueryf(vi_spec,"CALC:MARK:Y?\n","%t",buf);?
viPrintf(vi_spec,"*WAI\n");? 
viPrintf(vi_spec,"INIT:CONT?ON\n");
viPrintf(vi_spec,?"SWE:TIME?2s\n");


//功率计 /*  
viPrintf(vi_boonton,"SENS:CORR:OFFS 31dBm\n");//外部补偿电平 
viPrintf(vi_boonton,"DISP:TRAC:VCENT 55dBm\n");//参考电平 
viPrintf(vi_boonton,"TRIG:LEV 40dBm\n");//触发电平  
viPrintf(vi_boonton,"DISP:PULS:TIMEBASE 10us\n");//时间单位 
viPrintf(vi_boonton,"DISP:TRAC:VSCALe 5dB\n");//db/格 
viPrintf(vi_boonton,"*CLS\n");  
viPrintf(vi_boonton,"CALC:MODE PULSE\n");  
viPrintf(vi_boonton,"DISP:PARA:MODE MEAS\n");   
viPrintf(vi_boonton,"SENS:CORR:OFFS 0\n");//0dB//外部补偿电平 
viPrintf(vi_boonton,"TRIG:LEV 0\n");//触发电平  
viPrintf(vi_boonton,"DISP:TRAC:VCENT 0\n");//参考电平 
viPrintf(vi_boonton,"DISP:TRAC:VSCALe 5\n");//db/格10 
viPrintf(vi_boonton,"TRIG:DEL 0\n");//触发事件位置s 0  
viPrintf(vi_boonton,"DISP:PULS:TIMEBASE 5us\n");//pow 
viPrintf(vi_boonton,"DISP:PULS:TIMEBASE 5us\n"); 
viPrintf(vi_boonton,"*WAI\n");  
// viQueryf(vi_boonton,"FETCH:INTER:MAX ?\n","%t",buf); 
viQueryf(vi_boonton,"FETCH:ARRAY:AMEA:POW  ?\n","%t",buf);


viPrintf(vi_boonton,"TRIG:SLOP POS\n");  
viPrintf(vi_boonton,"DISP:PULS:TIMEBASE 100ns\n"); 
viPrintf(vi_boonton,"*WAI\n");  
viQueryf(vi_boonton,"FETCH:ARRAY:AMEA:TIM ?\n","%t",buf_time); 
viQueryf(vi_boonton,"FETCH:INTER:MAX ?\n","%t",buf_p);//0410 
viQueryf(vi_boonton,"FETCH:ARRAY:AMEA:POW  ?\n","%t",buf_p); 
viPrintf(vi_boonton,"*WAI\n"); 
str_time=buf_time;count=0;   


/////////////////////////测试下降沿  
viPrintf(vi_boonton,"TRIG:SLOP NEG\n"); 
viPrintf(vi_boonton,"*WAI\n");  
viQueryf(vi_boonton,"FETCH:ARRAY:AMEA:TIM ?\n","%t",buf_time); 
viQueryf(vi_boonton,"FETCH:ARRAY:AMEA:POW  ?\n","%t",buf_p2); 
//viQueryf(vi_boonton,"FETCH:INTER:MAX ?\n","%t",buf_p2);//均值
viPrintf(vi_boonton,"*WAI\n");?
//viQueryf(vi,"FETCH:INTER:AVER?\n","%t",buf);READ:INTER:AVER?
viQueryf(vi,"FETCH:INTER:MAX?\n","%t",buf);?READ:INTER:MAX??


//////////////////////////////////////////////////////?
viPrintf(vi_zvb,?"SYST:DISP:UPDate?ON\n");?
viPrintf(vi_zvb,?"SWE:COUnt?%d\n",m_point);? 
viPrintf(vi_zvb,?"CALC:PAR:SEL?'CH1_S11_1'\n");?
viPrintf(vi_zvb,?"CALC:PAR:DEF?'My_S11',s11\n");?
//////? 
viPrintf(vi_zvb,?"CALCulate1:PARameter:SELect?'Ch1Trc2'?'S21'\n");?? 


viPrintf(vi_zvb,?"SYST:DISP:UPDate?ON\n");?
viPrintf(vi_zvb,?"CALC:FORM?PHAS\n");


viPrintf(vi_zvb,?"FORMat?ASCII\n");? 
viQueryf(vi_zvb,?"INITiate1:CONTinuous?OFF;*OPC?\n","%",?ValueStr);?
viPrintf(vi_zvb,?"SENS1:FREQ:STAR?1000MHz\n");?
viPrintf(vi_zvb,?"SENS1:FREQ:STOP?1125MHz\n");?
viPrintf(vi_zvb,?"SENS1:SWE:POIN?126\n");?
viPrintf(vi_zvb,?"OUTP1??OFF\n");?
viPrintf(vi_zvb,?"SOUR:POW?-7\n");?
viPrintf(vi_zvb,"CALC1:MARK1?ON\n");