Objective Development Forums

_frank26080115 wrote:have you tried break-pointing right before "ControlTransfer" and examining the packet before it's sent?

_frank26080115 wrote:I have great success using LibUsbDotNet, I have made an LCD display which uses control transfers for text, brightness, and contrast setting, when I did it, I always made sure that the values for bmRequestType and bRequest were valid, it sounds like you are just putting in values from textboxes, are the values valid?

_frank26080115 wrote:why are you always explicitly casting the UsbDevice object to interfaces? why not just call methods on usbDevice?

I'll install the lightweight debugger.

public bool SetContrast(byte contrast)
        {
            if (IsConnected == false)
                return false;

            UsbSetupPacket packet = new UsbSetupPacket((byte)UsbRequestType.TypeVendor, (byte)RequestCommand.SetContrast, (short)contrast, 0, 0);
            int temp1;
            object temp2 = null;
            return MyUsbDevice.ControlTransfer(ref packet, temp2, 0, out temp1);
        }

_frank26080115 wrote:

here's a bit from my own code

Code: Select all

public bool SetContrast(byte contrast)
        {
            if (IsConnected == false)
                return false;

            UsbSetupPacket packet = new UsbSetupPacket((byte)UsbRequestType.TypeVendor, (byte)RequestCommand.SetContrast, (short)contrast, 0, 0);
            int temp1;
            object temp2 = null;
            return MyUsbDevice.ControlTransfer(ref packet, temp2, 0, out temp1);
        }