Astronics 407661-001, Руководство пользователя

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1260-114 User Manual Publication No. 980824-114 Rev. A
Module Operation 3-6 Astronics Test Systems
value in the range from 1 and 12 inclusive.
3. The 1260-114 port or control register to be written to or read
from. Each register on the 1260-114 has a unique offset from
the base address.
The base A24 address for the 1260-114 module may be calculated
by:
(A24 Offset of the 1260-01T) + (1024 x Module Address of
1260-114).
The A24 address offset is usually expressed in hexadecimal. A
typical value of 204000
16
is used in the examples that follow.
A 1260-114 with a module address of 7 would have the base A24
address computed as follows:
Base A24 Address of 1260-114 = 204000
16
+ (400
16
x 7
10
)
= 205C00
16
The port and control registers for Adapt-a-Switch plug-ins and
conventional 1260-Series modules are always on odd-numbered
A24 addresses. For port registers, the 1260-114 reads and writes
to the same location. For control registers, the 1260-114 writes to
one location, but reads back from another.
Table 3-1 provides
offsets relative to the base address of the module for all port and
control registers of the 1260-114. To obtain the absolute address
where data is to be written or read from, the base address is
added to the offset:
(Base A24 1260-114 Address) + offset = absolute address
So, for our example base A24 address computed earlier, the
following absolute addresses would apply for the operations
indicated:
205C01 Port 0 read or written at this location
205C19 Control Register 1 written at this location
205E03 Control Register 1 read at this location
Before explaining the particulars of reading and writing to port and
control registers, it is necessary to understand how the registers
interact with the 1260-114.
Table 3-2 provides a detailed
explanation of each register and how it interacts with the 1260-114
module.