说明：  这是VB编程RS232串口（COM口）控制的D/A(数模转换)转换板的上位机演示程序。通过电脑串口（或其他具有串口的单片机、PLC、DSP）发个简单的可视ASCII指令，便可以方便地控制8个数模转换通通道输出设定的电压值。比如,电脑串口输出字符串"C2V2660"到本控制板,则控制板将控制2号通道输出2.66V电压；电脑串口输出字符串"C6V3060"到本控制板,则控制板将控制6号通道输出3.06V
(This is the host computer demo program VB programming RS232 serial port (COM port) to control the D/A (digital to analog conversion) converter board. Send a simple visualization of ASCII commands through the computer serial port (or other serial microcontroller, the PLC, DSPs), we can easily control the voltage value set by eight the number of analog conversion channel output. For example, the computer serial output string C2V2660 to this control panel, control panel will control the 2nd channel output 2.66V voltage computer serial output string C6V3060 to the control panel, control panel will control 6 channel output 3.06V)