The GX5642 driver functions reference chapter is organized in alphabetical order. Each function is presented starting with the syntax of the function, a short description of the function parameters description and type followed by a Comments, an Example (written in C), and a See Also sections.
All function parameters follow the same rules:
Strings are ASCIIZ (null or zero character terminated).
Most function’s first parameter is nHandle (16-bit integer). This parameter is required required for operating the board and is returned by the Gx5642Initialize or the Gx5642InitializeVisa functions function. The nHandle is used to identify the board when calling a function for programming and controlling the operation of that board.
All functions return a status with the last parameter named pnStatus. The pnStatus is zero if the function was successful, or less than a zero on error. The description of the error is available using the GXPIOGetErrorString function or by using a predefined constant, defined in the driver interface files: GXPIO.H, GXPIO.BAS, GXPIO.PAS or GX5642.DRV.
Parameter name are prefixed as follows:
Prefix |
Type |
Example |
a |
Array, prefix this before the simple type. |
anArray (Array of Short) |
n |
SHORT (signed 16-bit) |
nMode |
d |
DOUBLE - 8 bytes floating point |
dReading |
dw |
DWORD - double word (unsigned 32-bit) |
dwTimeout |
hwnd |
Window handle (32-bit integer). |
hwndPanel |
l |
LONG (signed 32-bit) |
lBits |
p |
Pointer. Usually used to return a value. Prefix this before the simple type. |
pnStatus |
sz |
Null (zero value character) terminated string |
szMsg |
w |
WORD. Unsigned short (unsigned 16-bit) |
wParam |
hwnd |
Window handle (32-bit integer). |
hwndPanel |
Parameter Prefixes