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An example how to use Windows API to control a serial port or a USB VCP device from VB6 or VBA Word, Excel, Access. The code below shows how to declare WinAPI data. Chipmunk Basic Man Page BASIC1 Chipmunk Basic v3. BASIC. You need to know the address of the port you want to use. You will also need two other things the command to access the port and the number you want to set it to. This is the newest revision of our FTDI Basichttpswww. We now use a SMD 6pin header on the bottom, which makes i. Programming The Parallel Port In Visual Basic. If you have built any of the interfaces on my circuits page and now want to know how to actually make use of them, this page is for you. This is a simple introduction to programming the parallel port in Visual Basic. Note that most of the concepts in this page apply to both 1. VB. If you are interested in using QBasic to control the port, see Programming The Parallel Port In QBasic. What this document will not do is give you lots of details on using bi directional ports, DMA and other advanced topics. This document assumes that you are familiar with the basic functions of Visual Basic itself. Now before we go any further, we must figure out a way around some limitations built into Visual Basic. VB cannot directly access the hardware on a system. All hardware requests must go through Windows. Because of this, the closest we can get to manipulating the parallel port is with the Printer object. While this is all fine and good when you want to actually print something, it is useless when we want direct hardware control. There may be API calls to get round this, but as of yet I have been unable to find any. In order to control the port directly, we must use something external to our program. It just so happens that there is a great, free product that does exactly what we want. It is a DLL from a company called Soft. Circuits. You can download this DLL from their Programming Tools and Libraries page. Use VBASM. DLL in the VBASM. ZIP package for VB1, VB2, VB3 or VB4 1. Bit. Use WIN9. 5IO. DLL in the WIN9. IO. ZIP package for VB4 3. KB/boards-embedded-devices/834674/2.5.jpg' alt='Basic Serial Port Programming' title='Basic Serial Port Programming' />VB5 or VB6. No matter which one you choose, the DLL file itself must be in the windowssystem directory in any machine the interface control software is to be used or developed on. Please note that no matter which DLL you use, this wont work under any Windows NT based system, including Win. NT, Win. 2K, XP, Vista, Win. Windows Server. NT based systems do not allow direct hardware access to non drivers. Serial Port Control Easy to use developer component intended for simplification serial port communication tasks in your projects. Now that we have that finished with, lets get to the port. The parallel port is made up of three different sections. These are the data lines, control lines and status lines. There are 8 data lines, and they are the primary means of getting information out of the port. Visual Basic Serial Port Programming' title='Visual Basic Serial Port Programming' />In simple projects, you will be concentrating mostly on the data lines. The control lines are another 4 outputs. They are meant to provide control signals to the printer such as form feed or initialize. Before this Ive always used the Serial Monitor of the Arduino IDE to communicate with the Arduino. Actually what the Serial Monitor does is basically reading or. The status lines are a standard parallel ports only inputs. There are 5 of them. They were meant to allow the printer to communicate things such as error, paper out and busy to the PC. Each section is accessed by its own address and will act independently from the rest. This is almost as if they were different ports. El Diluvio Del Genesis Pdf. The addresses are as follows. Visual Basic Serial Port Programming Example' title='Visual Basic Serial Port Programming Example' />Port. Address DecimalAddress HexData Lines. Control Lines. 89. Ah. Status Lines. You need to know the address of the port you want to use. You will also need two other things the command to access the port and the number you want to set it to. The command will be explained in a little while. The ports work with numbers. These can be expressed in hex, binary or decimal, but for this document all values will be expressed in decimal. Its just easier that way. Anyway, you operate the port by sending it a number that represents the binary pattern of the physical outputs on the port. For example, to set the 8 data lines to 1. To set them to 0. Note that these are all 8 bit binary numbers, and the port is also 8 outputs. Coincidence I think not. Before we can use any of the functions contained within either DLL, we must declare them. These declarations are to be placed in any module in your program in the GeneralDeclarations section. For 1. 6bit VB VBASM. Top 1000 World Banks 2010 Pdf. DLL, use. Declare Function vb. Inp Lib VBASM. DLL By. Val n. Port As Integer As Integer. Declare Sub vb. Out Lib VBASM. DLL By. Val n. Port As Integer, By. Val n. Data As Integer. For 3. 2bit VB WIN9. IO. DLL, use. Declare Sub vb. Out Lib WIN9. 5IO. DLL By. Val n. Port As Integer, By. Val n. Data As Integer. Declare Sub vb. Outw Lib WIN9. IO. DLL By. Val n. Port As Integer, By. Val n. Data As Integer. Declare Function vb. Inp Lib WIN9. 5IO. DLL By. Val n. Port As Integer As Integer. Declare Function vb. Inpw Lib WIN9. 5IO. DLL By. Val n. Port As Integer As Integer. Once you declare the functions, you will have two new commands available. These are vb. Inp and vb. Out. vb. Out is a statement and is used to send a bit to a port, like the following. Microsoft Office Word 2007 Crack Torrent. Out port,number. We will get to vb. Inp later. As you can see, the two parameters required are the port address and the value we want to set it to. The address can be decimal or hex, as can the value. Because there are only 8 data lines, we can only send a maximum of 2. The examples below illustrate sending a few different bit patterns to the data lines. Of course, you can also turn on more than one bit. Note that when you send a bit pattern to the port everything that was there previously is cleared. This is a convenience and also a annoyance. For example, what if we want bit 2 to always stay at 1, but want to turn bit 5 on and off in sequence Every time we set bit 5, bit 2 is turned off, and vice versa. We will discuss how to get around this when we get to the vb. Inp function. The control lines are just as easy to control, but there are a few differences. First, the address of the port is 8. Second is that there are only 4 outputs, so the highest decimal representation of the binary bit pattern you will be using is 1. Outputting information is easy, and inputting is just as easy. If you actually want to get information into the computer, you will be using the 5 status lines. Reading the bit pattern of a port is done using the vb. Inp function. This function is used in the following way. Inpport. So if we wanted to get the current status of the status lines port 8. Port. Numvb. Inp8. Port. Num would then contain the decimal representation of the binary bit pattern present at the 5 status lines. If you try this and get 3. When there is nothing connected to the input of a TTL logic chip, a high input is usually assumed. Not only can you perform inputs on ports actually designed for inputting, but you can also use vb. Inp to read the status of an output port. For example. Port. Numvb. Inp8. 88. The above would set Port. Num to the current value of the data lines port 8. We can prove this by doing the following. Port. Numvb. Inp8. Msg. Box Port. Num. If all is well, the number 5. Now that we know the vb. Inp function we can use it to solve the problem of keeping the state of one bit while changing the state of another. For that we will define a subroutine that uses both functions. SUB Out. PortPort. Address, Out. Num. Port. State vb. InpPort. Address. Port. Num Port. State Out. Num. Out Port. Address, Port. Num. Note how the sub adds the current port state to the number we send it. This has the effect of keeping all previous bits at the same state they were in, but either turning on or off the bit or bits represented by the number we pass to the sub. This also requires a change in the way the function is used. To turn on bit 1, we would. This example assumes a current port status of 0 0. If bit 1 is already high, you will get unexpected results, so keeping track of the port is important. To turn bit 1 back off, we would. Out. Port 8. 88, 1. Now this sub introduces a problem. How do we clear everything on the port as if we were doing vb. Serial Port Programming With. NET 6 Steps. We need to include two namespaces in order to use the Serial. Port class using System. IO. Ports using System. IO We now need to instantiate a Serial. Port object. There are several constructors to choose from to specify different frame formats but in general the easiest to use is the following Serial. Portstring port. Name, int baud. RateAn example of this would be Serial. Port my. Serial. Port new Serial. Port COM3, 9. 60. Here I am using COM3 at 9. You can find the full list of constructors in the link in the intro. Now that we have created our Serial. Port object, we need to open the port using the Open method. When we are done we will want to close it using the Close method my. Serial. Port. Open my. Serial. Port. Close Several notes when you use any operation that uses a serial port there is a good chance that an error will occur. For this reason we want to write our code for the serial port within a try catch block. This will prevent our program from crashing if, for example we tried to open a port that didnt exist. It is not necessary to instantiate our object within the try catch block, but we want to open, close, read, and write within it. Serial. Port object then opens and closes the port. Serial. Port my. Serial. Port new Serial. Port COM3, 9. Serial. Port. Open my. Serial. Port. Close catch IOException exConsole. Write. Lineex Thats really all there is for port setup In the next step we will introduce how to read from a serial port.