The GXFPGA 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 for operating the board and is returned by the GxFpgaInitialize or the GxFpgaInitializeVisa functions. 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 GxFpgaGetErrorString function or by using a predefined constant, defined in the driver interface files: GXFPGA.H, GXFPGA.BAS, GXFPGAVB, GXFPGA.PAS or GXFPGA.DRV.
Parameters names 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 |
Double word (unsigned 32-bit). |
dwTimeout |
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 |
Unsigned short (unsigned 16-bit). |
wParam |
hwnd |
Window handle (32-bit integer). |
hwndPanel |
Parameter Prefixes