ERMP

Enable Read Multiple

2

 

Setting this bit causes Read Multiple commands to be

 

 

issued on the PCI bus after certain conditions have been

 

met. These conditions are described in Chapter 3, “PCI

 

Functional Description.”

 

BOF

Burst Opcode Fetch Enable

1

 

Setting this bit causes the LSI53C810A to fetch

 

 

instructions in burst mode, if the Burst Disable bit (Chip

 

Test Four (CTEST4), bit7) is cleared. Specifically, the chip

 

bursts in the first two Dwords of all instructions using a

 

 

single bus ownership. If the instruction is a Memory-to-

 

 

Memory Move type, the third Dword is accessed in a

 

 

subsequent bus ownership. If the instruction is an indirect

 

type, the additional Dword is accessed in a subsequent

 

bus ownership. If the instruction is a table indirect block

 

move type, the chip accesses the remaining two Dwords

 

in a subsequent bus ownership, thereby fetching the four

 

Dwords required in two bursts of two Dwords each.

 

MANManual Start Mode0

Setting this bit prevents the LSI53C810A from automatically fetching and executing SCSI SCRIPTS when the DMA SCRIPTS Pointer (DSP) register is written. When this bit is set, the Start DMA bit in the DMA Control (DCNTL) register must be set to begin SCRIPTS execution. Clearing this bit causes the LSI53C810A to automatically begin fetching and executing SCSI SCRIPTS when the DMA SCRIPTS Pointer (DSP) register is written. This bit normally is not used for SCSI SCRIPTS operations.

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LSI 53C810A technical manual Ermp, Bof, Burst Opcode Fetch Enable, MANManual Start Mode0