Wait Select Instruction

1.If the LSI53C810A is selected, it fetches the next instruction from the address pointed to by the DMA SCRIPTS Pointer (DSP) register.

2.If reselected, the LSI53C810A fetches the next instruction from the address pointed to by the 32-bit jump address field stored in the DMA Next Address (DNAD) register. Manually set the LSI53C810A to Initiator mode when it is reselected.

3.If the CPU sets the SIGP bit in the SCSI Status Zero (SSTAT0) register, the LSI53C810A aborts the Wait Select instruction and fetches the next instruction from the address pointed to by the 32-bit jump address field stored in the DMA Next Address (DNAD) register.

Set Instruction

When the SACK/ or SATN/ bits are set, the corresponding bits in the SCSI Output Control Latch (SOCL) register are set. Do not set SACK/ or SATN/ except for testing purposes. When the target bit is set, the corresponding bit in the SCSI Control Zero (SCNTL0) register is also set. When the carry bit is set, the corresponding bit in the Arithmetic Logic Unit (ALU) is set.

Note: None of the signals are set on the SCSI bus in Target mode.

I/O Instruction

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LSI 53C810A technical manual Wait Select Instruction, Set Instruction