Aim MIL-STD-1553 - 7.1 Low Speed Functions

MIL-STD-1553 Reference Manual
181
Chapter 5 – Buffer Functions
5.1.17 ApiReadMemData
Prototype:
AiInt16 ApiReadMemData( AiUInt32 ul_ModuleHandle, AiUInt8 memtype, AiUInt32 offset,
AiUInt8 width, void* data_p);
Driver Command:
none
Purpose:
This function is used to read a byte/word/longword data value from AIM board memory
in avoidance of AIM board command and acknowledge interface access. This is
necessary to access the board memories in case of interrupt. The function does a
direct access to the AIM board memory at the specified offset address .
I
I
n
n
p
p
u
u
t
t
A
A
i
i
U
U
I
I
n
n
t
t
8
8
m
m
e
e
m
m
t
t
y
y
p
p
e
e
Memory Type to be accessed
Value
Constant
Description
0
API_MEMTYPE_GLOBAL
Global Memory access
1
API_MEMTYPE_SHARED
Shared Memory access
2
API_MEMTYPE_LOCAL
Local Memory access
3
4
5
API_MEMTYPE_IO
API_MEMTYPE_GLOBAL
_DIRECT
API_MEMTYPE_GLOBAL
_EXTENSION
IO/Galileo Memory access
Direct access to Global Memory
even if there is a mirror
Global Memory Extension
access
Note: not all memory types are available for all boards.
A
A
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i
U
U
I
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n
n
t
t
3
3
2
2
o
o
f
f
f
f
s
s
e
e
t
t
Byte offset address relative to the start of a specific onboard memory described in
parameter ‘memtype’.
A
A
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U
U
I
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n
n
t
t
8
8
w
w
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h
h
Data width of access
Value
synonym
Description
1
sizeof(AiUInt8)
Byte data access
2
sizeof(AiUInt16)
Word data access
4
sizeof(AiUInt32)
Longword data access
O
O
u
u
t
t
p
p
u
u
t
t
v
v
o
o
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d
d
*
*
d
d
a
a
t
t
a
a
_
_
p
p
Data to read to. This pointer should match to the data size given in the parameter
width.
Note: Be sure to have allocated enough memory referenced by this pointer
within the application!