TSI Incorporated 8587A, Руководство по эксплуатации и обслуживанию

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Technical Information for Program Development Using USB Communications C-9
Parameter Description Type
hDevice
The handle to the connected device
returned from DeviceOpen().
HANDLE
pRecvBuff
A pointer to a buffer for receiving the data
read from the device.
LPVOID or void*
recvBuffSize
The size of the buffer for receiving data
read from the device.
DWORD or Unsigned long
pTransID
The transaction ID of this read transfer. The
transaction ID is a value 0x80
– 0xff that
will allow matching a response to a request.
This is defaulted to 0x80 and only
necessary for asynchronous responses.
LPWORD or pointer to an
unsigned long
pLevelID
The Level ID of this read transfer. The level
ID is an indication of what type of response
was received. i.e., (data, an error, a
warning, etc.).
See the List of level Id’s
below.
LPWORD or pointer to an
unsigned long
pStatus
A pointer to the status returned from the
device. PULONG or pointer to an
unsigned long
lpNumberOfBytesRead
A pointer to the number of bytes read from
the device. LPDWORD or pointer to an
unsigned long
wEndpoint
The index of the device endpoint to read
from. Unless this is documented as
different use the default endpoint.
WORD
Return value:
A successful return Win32 Error Code value is Zero or ERROR_SUCCESS
A non-successful return Win32 Error Code value is non-zero corresponding
to any valid Win32 Error Code.
This command does have a Status return from the device. A returned
status (referenced by pStatus) of 0x0000 or USB_OK as well as a win32 is
a successful return of ERROR_SUCCESS is a successful device terminal
receive request.
This response should always return a *pStatus of
USB_OK.
The following is a list is level Ids
USB_TERMINAL_RESPONSE 0x81
USB_TERMINAL_ERROR 0x82
USB_TERMINAL_WARNING 0x83
USB_TERMINAL_INFORMATION 0x84
USB_TERMINAL_BINARY_DATA 0x8f