Re: USB Missile launcher

["Björn Lundin" <b.f.lundin@gmail.com>]

On 2014-10-29 18:43, kadrickhenderson008@yahoo.com wrote:


The device connects to the pc via USB.


I've had success running the K8055 boards from Velleman via
libusb both on Windows and Linux.

It came with a driver/dll but if I remember correctly,
I had to loop through all usb looking at Vendor and device
interfaceing.

Looking around I can't find the code at work, might be at home.
But for the linux part, I took the c-code from
http://sourceforge.net/projects/libk8055
and rewrote it (parts of it) in Ada.
And one part was to get hold of the correct usb,
and open it. (The library supports 4 cards)


libk8055.c function OpenDevice
should give you some ideas.

The data passing mechanism is of course different,
But the 8055 has


/* globals for datatransfer */
struct k8055_dev {
    unsigned char data_in[PACKET_LEN+1];
    unsigned char data_out[PACKET_LEN+1];
    struct usb_dev_handle *device_handle;
    int DevNo;
};


and is written to by
/* Actual write of data to the device endpont, retry 3 times if not
reponding correctly */
static int WriteK8055Data(unsigned char cmd)
{
    int write_status = 0, i = 0;

    if (CurrDev->DevNo == 0) return K8055_ERROR;

    CurrDev->data_out[0] = cmd;
    for(i=0; i < 3; i++)
        {
        write_status = usb_interrupt_write(CurrDev->device_handle,
USB_OUT_EP, (char *)CurrDev->data_out, PACKET_LEN, USB_TIMEOUT);
        if (write_status == PACKET_LEN) return 0;
        if (DEBUG)
            fprintf(stderr, "Write retry\n");
        }
    return K8055_ERROR;
}

where I think usb_interrupt_write is libusb


the datastructure for your missile is perhaps
found in https://code.google.com/p/thunder-missile-api/

and MissileLauncher.cs from there idicates
* HID interface by         private UsbHidPort USB;
* The data structure , which seems to be treated as a bytearray

There are other libraries out there to see the actual protocol.

I'll see if I can find the usb-connecting code I did in Ada


--

Björn