parallel-port

问题 I am developing an application which would redirect i/o from parallel port of, say, device A to the parallel port of device B . The two devices are connected on ethernet (LAN, WAN, internet, etc.). Device A has a physical parallel port attached to it but device B is a machine with no parallel port on it. This is what makes me emulate a parallel port on device B such that windows thinks that it has a parallel port and works in the very manner with it as it works with parallel ports on hardware

问题 For one of my projects, that is related to nerve conduction study, I need to acquire data continuously from a parallel printer port in Windows XP. The analogue data is processed by an Analogue to Digital converter and then serve it to parallel printer port. To get familiar with the data acquisition process I was trying to acquire data from a frequency signal generator that is connected to ADC and the frequency is set to 50 Hz. So far I have been able to read the data from PC using Java, but I

问题 I am trying to communicate with a Parallel Port via the package jnpout32reg (http://www.hytherion.com/beattidp/comput/pport.htm), a Java implementation of inpout32 (http://www.highrez.co.uk/downloads/inpout32/). I have tested inpout32 with a Parallel Port Tester (download. cnet. com/Parallel-Port-Tester/3000-2086_4-75940249.html), which seems to work perfectly. However, the java implementation does not seem to work. package ioTest_reg; import hardware.jnpout32.*; public class ioTestReg {

问题 I am trying to write a Chrome app that would support printing to old printers connected to the computer via the parallel port. I found out that Chrome apps can not use any kind of NPAPI plugins so those are out of the question. The remaining option seems to be NaCl or PPAPI plugin. But does PPAPI or pepper or NaCl (I am not very familiar with any of them and am probably using them in the wrong context) support access to the parallel port? Can a PPAPI plugin be written, which supports parallel

问题 I am wondering how to set the data pins on a parallel port high and low. I believe I could use PyParallel for this, but I am unsure how to set a specific pin. Thanks! 回答1: You're talking about a software-hardware interface here. They are usually set low and high by assigning a 1-byte value to a register. A parallel port has 8 pins for data to travel across. In a low level language like C, C++, there would be a register, lets call it 'A', somewhere holding 8 bits corresponding to the 8 pins of

问题 I don't get any error or exception. Button in one Window: private void button1_Click(object sender, EventArgs e) { ControlPort.Output(0x378, 0xff); } and inpout.dll interface: class ControlPort { [DllImport("inpout32.dll", EntryPoint = "Out32")] public static extern void Output(int adress, int value); } What is wrong? LED on D2 is on all the time. I have Windows 7 x64 Ultimate. 回答1: For x64 you should use "InpOutx64.dll". Visit: http://www.highrez.co.uk/Downloads/InpOut32/default.htm There

问题 I have to count the input frequency of the parallel port at Pin no.13, comming from a 555 timer IC, the real frequency should be around 3-4 Hz (ON Pulse). I have tried several codes, several times but every time those are giving different values. I have tried the following code: [DllImport("inpout32.dll", EntryPoint = "Inp32")] public static extern int Input(int adress); private void button1_Click(object sender, EventArgs e) { int currentState = Input(889); int LastState; while (true) { int

问题 how to control data bits of a parallel port via java.actually i am making a project on " WEB BASED POWER HANDLING" in which i have to control devices remotely from other machines over internet through parallel port progrmming.any help? 回答1: There is not a standard Java API for handling the parallel port so you will have to have the underlying operating system help you. Most operating system allows talking to external devices - Windows through the "PRN" magic name, Linux through various /dev

问题 I am writing an activex control that will access the parallel port and write the bytes to it. I am able to open the port succesfully but when i write it hangs at WriteFile function. Did i miss anything here? I am using Windows 7 HANDLE portHwd = CreateFile( _T("\\\\.\\LPT1" ), GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL); if (portHwd) { char outBuffer[] = _T("This is a test\r\n"); int sz_buffer = strlen(outBuffer); DWORD bytes_written; if (!WriteFile( portHwd, outBuffer, sz_buffer , &bytes

问题 I have a USB to parallel port device that i want to interface with through c++ on a modern windows OS (xp and newer). I've done a little research but the information is a bit patchy when it comes to programming to one of these USB to parallel port devices (most of the information is dated and assumes that you have a parallel port built right into the motherboard, something my brand new computer doesn't have). One reference even says that it is not possible to interface with a USB to parallel