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Embedded Coder Support Package for Green Hills MULTI IDE (R2012b)

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Embedded Coder Support Package for Green Hills MULTI IDE (R2012b)

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Embedded Coder integration for creating models that run directly in Green Hills MULTI IDE

read(id,address,datatype,count,timeout)
function resp = read(id,address,datatype,count,timeout)
%READ Retrieves a block of data values from processor memory.
%  MEM = READ(id,ADDRESS,DATATYPE,COUNT,TIMEOUT) returns a block of data 
%  values from the memory space of the target processor referenced by the id
%  object.  The blocks to read begins from the processor memory location 
%  given by the ADDRESS parameter.  The data format of the raw memory image
%  is specified by the DATATYPE option.  Read multiple blocks of data
%  values by specifying a COUNT parameter.
%
%  ADDRESS is a decimal or hexadecimal representation of a memory address in
%  the target processor.  In all cases, the full address consist of two 
%  parts: the offset and the memory page.  Many processors have only a 
%  single memory page, in which case the page portion of the full address 
%  should always be 0.  The page value can be explicitly defined using a 
%  numeric vector representation of the address.  Alternatively, the id 
%  object has a default page value that is applied if the page value is not 
%  explicitly incorporated into the passed address parameter.  In
%  processors with only a single page, by setting the id object page value
%  to zero it is possible to specify all addresses using the abbreviated 
%  (implied page) format.  The address parameter can be specified in two 
%  ways, first as a numerical value which is a decimal representation of 
%  the processor address.  Alternatively, a string is interpreted as a 
%  hexadecimal representation of the address offset.  (See HEX2DEC, which is
%  used for the conversion to a decimal value).  When the address is defined
%  by a string, the page is always derived from the id object.  Thus, there
%  is no method of explicitly defining the page when the address parameter 
%  is passed as a hexadecimal string.
%
%  Examples of the address parameter:
%     '1F'  Hex, Offset is decimal 31, with the page taken from id.page.
%       10  Decimal, Offset is decimal 10, with the page taken from id.page.
%   [18,1]  Decimal with page, Offset is decimal 18, with page equal to 1.
%
%  DATATYPE defines the interpretation of the raw values read from the 
%  processor memory. The data is read starting from ADDRESS without regard
%  to type-alignment boundaries in the processor.  Conversely, the byte 
%  ordering of the data type is automatically applied. The following MATLAB
%  data types are supported:
%
%    'double'  IEEE Double-precision floating point
%    'single'  IEEE Single-precision floating point
%     'uint8'  8-bit unsigned binary integer
%    'uint16'  16-bit unsigned binary integer
%    'uint32'  32-bit unsigned binary integer
%      'int8'  8-bit signed 2's complement integer
%     'int16'  16-bit signed 2's complement integer
%     'int32'  32-bit signed 2's complement integer
%
%  The COUNT parameter defines the dimensions of the returned data block 
%  (MEM).  COUNT can be a scalar value which causes read to return a column 
%  vector which has COUNT values.  Multidimensional reads are possible by 
%  passing a vector for COUNT.  The elements of count define the dimensions 
%  of the returned data matrix.  The memory is read in column-major order.  
%  COUNT defines the dimensions of the returned data array (MEM) as follows:
%
%           n  Read n values into a column vector.
%       [m,n]  Read m-by-n values into m by n matrix in column-major order.
%   [m,n,...]  Read a multidimensional matrix of values.
%
%  The TIMEOUT parameter defines how long to wait (in seconds) for the 
%  read to complete.  If this period is exceeded, the routine returns
%  immediately with a timeout error.  
%
%  MEM = READ(id,ADDRESS,DATATYPE,COUNT) Same as above, except the timeout
%  value defaults to the value specified by the id object. Use 
%  GET(id, 'timeout') to examine the default supplied by the object.
%
%  MEM = READ(id,ADDRESS,DATATYPE) Same as above, except the count value 
%  defaults to one value of type DATATYPE.
%
%  This routine does not coerce data type alignment.  Certain combinations
%  of ADDRESS and DATATYPE are difficult for the processor to use.  To
%  ensure seamless operation, best practice is to use the ADDRESS method to
%  extract address values that are compatible with the alignment 
%  requirements of the processor.
%
%  Examples
%   1. Read one 16-bit integer 'var'.
%      mlvar = read(id,address(id,'var'),'int16');
%   2. Read and plot 100 integers (32-bits) from address 0xF000.
%      mlplt = read(id,'F000','int32',100);
%      plot(double(mlplt));
%   3. Increment integer value at address 10 (decimal) of target processor.
%      mlinc = read(id,10,'int32');
%      mlinc = int32(double(mlinc)+1);
%      write(id,10,mlinc);
%
%  See also GHSMULTI/WRITE, GHSMULTI/ADDRESS, HEX2DEC, INT32.

%   Copyright 2012 The MathWorks, Inc.

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