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Futterama
Joined: 17 Oct 2005
Posts: 98
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| Use bytes from array as int16 and int32 |
 Posted: Sat Feb 18, 2017 2:55 pm |
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Hi,
I receive some chars over RS232 and save those in a byte array.
Some of the data is a int16 (2 bytes) and some is a int32 (4 bytes).
How can I access the bytes in the array as int16 and int32 types without having to save it in a separate variable?
Example:
| Code: |
int8 array[6];
array[0] = 0x01;
array[1] = 0x02;
array[2] = 0x0A;
array[3] = 0x0B;
array[4] = 0x0C;
array[5] = 0x0D;
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In the above array[0]-[1] contains the int16 and array[2]-[5] contains the int32.
So how can I access these data directly as the int16 and int32 data types for use in e.g. a printf?
Thanks. |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19513
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| Posted: Sat Feb 18, 2017 3:01 pm |
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Use a union.
Create your own union for the array. So something like:
| Code: |
//If the array was (say) 128 bytes
union {
int8 characters[128];
int16 words[64];
int32 long_words[32];
} array;
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Then you have array.characters[] 0 to 127, array.words[] 0 to 63, and array.long_words[] 0 to 32, all talking to the same area of memory. |
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temtronic
Joined: 01 Jul 2010
Posts: 9226
Location: Greensville,Ontario
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| Posted: Sat Feb 18, 2017 3:02 pm |
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one way would be to use the builtin functions of make16() and make32().
press F11 while your project is open to access the manual,select make16() from the index....
Jay |
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Futterama
Joined: 17 Oct 2005
Posts: 98
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| Posted: Sat Feb 18, 2017 3:15 pm |
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| Thanks! |
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