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Theory of Operation
X64-AN Quad User's Manual
with a line rate of 15kHz would generate too many events for the PC to follow. The Sapera event
value is CORACQ_VAL_EVENT_TYPE_END_OF_LINE.
End of ‘n’ Lines
The End of ‘n’ Lines event is generated at the end of a group of ‘n’ lines transferred from onboard
memory into PC memory. Note that this event should only be used with slow line rates. The Sapera
event value is CORACQ_VAL_EVENT_TYPE_END_OF_NLINES.
Supported Transfer Cycling Methods
The
X64-AN Quad
supports the following transfer cycle modes which are either synchronous or
asynchronous. These definitions are from the Sapera Basic Reference manual.
CORXFER_VAL_CYCLE_MODE_SYNCHRONOUS_WITH_TRASH
Before cycling to the next buffer in the list, the transfer device will check the next buffer's state. If its
state is full, the transfer will be done in the trash buffer which is defined as the last buffer in the list;
otherwise, it will occur in the next buffer. After a transfer to the trash buffer is done, the transfer
device will check again the state of the next buffer. If it is empty, it will transfer to this buffer
otherwise it will transfer again to the trash buffer.
CORXFER_VAL_CYCLE_MODE_SYNCHRONOUS_NEXT_EMPTY_WITH_TRASH
Before cycling to the next buffer in the list, the transfer device will check the next buffer's state. If its
state is full, the next buffer will be skipped, and the transfer will be done in the trash buffer, which is
defined as the last buffer in the list; otherwise it will occur in the next buffer. After a transfer to the
trash is done, the transfer device will check the next buffer in the list, if its state is empty, it will
transfer to this buffer otherwise it will skip it, and transfer again to the trash buffer.
CORXFER_VAL_CYCLE_MODE_ASYNCHRONOUS
The transfer device cycles through all buffers in the list without concern about the buffer state.
