troubleshooting Question

How to retrieve ascii characters from modbus registers?

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naseeamFlag for United States of America asked on
1 Comment1 Solution341 ViewsLast Modified:
Twenty ascii characters are in Ten Modbus Registers.  Data in modbus registers is stored in little-endian.  Another words, Most Significant Byte(MSB) is farthest to the right (or last) and the Least Significant Byte(LSB) is farthest to the left (or first).

Example:  "Designate" is stored as follows in modbus registers:

Modbus Register 1:    e    D
Modbus Register 2:    i      s
Modbus Register 3:    n    g

unsigned short response_buffer[128];

/* The data in respone_buffer array should appear as follows:
response_buffer[0] = 'e'
response_buffer[1] = 'D'
response_buffer[2] = 'i'
response_buffer[3] = 's'
response_buffer[4] = 'n'
response_buffer[5] = 'g'                            */

/* Does following code retrieve the string properly  ?  Can this code be improved ?    */
char sco1[20];

for (short    i   =   0;     i    <    10;    i++)
   sco1 [ i ]  =   ( char )  ( ( response_buffer[  i  ]    &    0xFF);
   sco1 [ i ] =   ( char )  ( ( response_buffer [  i  ]    >>  8)  &   0xFF );
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