5-10
SCSI SCRIPTS Instruction Set
Target Mode
The LSI53C1000 verifies that it is connected to the SCSI
bus as a target before executing this instruction.
The LSI53C1000 asserts the SCSI phase signals
(SMSG/, SC_D/, and SI_O/) as defined by the Phase
Field bits in the instruction.
If the instruction is for the command phase, the
LSI53C1000 receives the first command byte and
decodes its SCSI Group Code.
•
If the SCSI Group Code is either Group 0,
Group 1, Group 2, or Group 5, then the LSI53C1000
overwrites the
register with
the length of the Command Descriptor Block: 6, 10, or
12 bytes.
•
If the Vendor Unique Enhancement 0 (VUE0) bit
(
, bit 1) is cleared and the
SCSI group code is a vendor unique code, the
LSI53C1000 overwrites the
register with the length of the Command Descriptor
Block: 6, 10, or 12 bytes. If the VUE0 bit is set, the
LSI53C1000 receives the number of bytes in the byte
count regardless of the group code.
•
If any other Group Code is received, the
register is not modified and the
LSI53C1000 requests the number of bytes specified
in the
register. If the DBC
register contains 0x000000, an illegal instruction
interrupt is generated.
The LSI53C1000 transfers the number of bytes specified
in the
register starting at the
address specified in the
register. If the Opcode bit is set and a data transfer ends
on an odd byte boundary, the LSI53C1000 stores the last
byte in the
register during
OPC
Instruction Defined
0
MOVE/MOVE64
1
CHMOV/CHMOV64
Содержание LSI53C1000
Страница 6: ...vi Preface...
Страница 16: ...xvi Contents...
Страница 28: ...1 12 Introduction...
Страница 234: ...4 124 Registers...
Страница 314: ...6 40 Specifications This page intentionally left blank...
Страница 318: ...6 44 Specifications This page intentionally left blank...
Страница 344: ...6 70 Specifications This page intentionally left blank...
Страница 350: ...6 76 Specifications Figure 6 42 LSI53C1000 329 Ball Grid Array Bottom view...
Страница 352: ...6 78 Specifications...
Страница 360: ...A 8 Register Summary...
Страница 376: ...IX 12 Index...