I've got some minimal C code that I wrote some time ago to talk to Siemens PLCs. I used it with a 1200. At the time I only hit I, M, and Q memory. I now need to go back and modify it to hit DB data block memory. I don't have the original documentation that I used to write it.
In one place I have codes for different data types.
I 0x81
M 0x83
Q 0x82
Two questions - the first is what is the code value for DB memory.
The second question - the two bytes in the packet for the DB number - do I send the low byte first or last?
Thanks to all.
In one place I have codes for different data types.
I 0x81
M 0x83
Q 0x82
Two questions - the first is what is the code value for DB memory.
The second question - the two bytes in the packet for the DB number - do I send the low byte first or last?
Thanks to all.