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The physical length of the regular stack is 768 16-bit words for CC-USB and 768 32-bit
words for VM-USB.
The physical length of the periodic (scaler) stack is 256 16-bit words for CC-USB and 256
32-bit words for VM-USB.
While the stack is expected to contain properly encoded sequence of CAMAC (CC-USB) or
VME (VM-USB) commands to be performed by XX-USB, it can store any sequence of
numbers.
6.8 xxusb_stack_read
The xxusb_stack_read function first, sends a buffer to XX-USB, causing the latter to write
the content of a desired stack to its USB port FIFO and then, obtains this content by reading a
buffer from the XX-USB.
WORD xxusb_stack_read{
HANDLE
hDevice,
WORD
wStackType,
LPDWORD
lpStackData
};
Parameters
hDevice
[in] Handle to the XX-USB device.
wStackAddress
[in] Type of the XX-USB stack, the content of which is to be read. Valid types are 0,
for the regular stack and 1, for the periodic (scaler) readout stack.
lpStackData
[out] Pointer to a variable array that receives the data returned by the operation, i.e., the
content of a XX-USB stack.
Return Values
On success, the function returns the number of bytes read from XX-USB. The valid value is
twice the length of the stack, as the latter stores 2-byte words.
Function returns a negative number on a failure.
6.9 xxusb_stack_execute
The xxusb_stack_execute function first, sends a buffer to XX-USB, causing the latter to
interprete its content as a series of simple and complex CAMAC commands and to actually
execute these commands and to write the returned CAMAC data to the USB port FIFO.
Then, xxusb_stack_execute reads a buffer from XX-USB, containing the desired CAMAC
data.
