Block Move Instructions
5-7
is combined with the data structure base address to
generate the physical address used to fetch values from
the data structure. Sign-extended values of all ones for
negative values are allowed, but bits [31:24] are ignored.
Note:
Using indirect and table indirect addressing simultaneously
is not permitted; use only one addressing method at a time.
Prior to the start of an I/O, load the
register with the base address of the I/O
data structure. Any address on a Dword boundary is
allowed.
After a Table Indirect opcode is fetched, the
is added to the 24-bit signed
offset value from the opcode to generate the address of
the required data; both positive and negative offsets are
allowed. A subsequent fetch from that address brings the
data values into the chip.
For a MOVE instruction, the 24-bit byte count is fetched
from system memory. Then the 32-bit physical address is
brought into the LSI53C1000. Execution of the move
begins at this point.
SCRIPTS can directly execute operating system I/O data
structures, saving time at the beginning of an I/O
operation. The I/O data structure can begin on any Dword
boundary and may cross system segment boundaries.
There are two restrictions on the placement of pointer
data in system memory:
•
The eight bytes of data in the MOVE instruction must
be contiguous.
•
Indirect data fetches are not available during
execution of a Memory-to-Memory DMA operation.
Command
Not Used
Don’t Care
Table Offset
00
Byte Count
Physical Data Address
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...