BitFlow Cyton-CXP, Hardware Reference Manual

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BUF_MGR_CON The Cyton-CXP
CYT-3-8 BitFlow, Inc. Version A.0
BM_RUN_LEVEL R/W, BUF_MGR_CON[3..0], Cyton-CXP
This is the main control for starting/stopping the Buffer Manager.
CURR_FETCH_
SIZE RO, BUF_MGR_CON[27..24], Cyton-CXP
This is the number of Quads that will be fetched at a time by the Buffer Manager. A
large read is issued over the PCIe bus to read all these Quads at one time.
MAX_FETCH_
SIZE RO, BUF_MGR_CON[31..28], Cyton-CXP
This is the maximum number of Quads that can be fetched as a group by the Buffer
Manager. The value in this register is derived as a function of the maximum PCIe read
request size set by PCI enumeration.
BM_RUN_LEVEL Meaning
0 (0000b) Idle - The Buffer Manager is not moving data
1 (0001b) Run - The Buffer Manger will start to move data
2 (0010b) Abort - Abort DMA and go to Idle
3 (0011b)
CURR_FETCH_SIZE Meaning
0 (0000b) 1 Quad
1 (0001b) 2 Quads
2 (0010b) 4 Quads
3 (0011b) 8 Quads
15 (1111b) 32K Quads