Hi all,
Got a new project with a Siemens S7-300 (CPU 312). I've just tried to copy in my motor control FB's from an S7-1200 project I did earlier in the year, and I've hit a speed bump in that my FB's use the "First Scan" tag from the system byte.
Now in the S7-1200, I selected which bit to use for the clock byte and the system byte, and the default tag table automatically created all the tags for first scan, always true/false, and all the pulsing tags.
In the S7-300, I can't find where to turn on the system byte, and though I've defined the clock byte, it doesn't show up in my tag table. So my questions are:
1. Does the S7-300 have a system byte available? If so, where do I activate it?
2. If not, is there another easy way of getting hold of a "first scan" bit without building my own?
3. How do I get the system byte (if it exists) and the clock byte to show up in my tag table?
Thanks!
Got a new project with a Siemens S7-300 (CPU 312). I've just tried to copy in my motor control FB's from an S7-1200 project I did earlier in the year, and I've hit a speed bump in that my FB's use the "First Scan" tag from the system byte.
Now in the S7-1200, I selected which bit to use for the clock byte and the system byte, and the default tag table automatically created all the tags for first scan, always true/false, and all the pulsing tags.
In the S7-300, I can't find where to turn on the system byte, and though I've defined the clock byte, it doesn't show up in my tag table. So my questions are:
1. Does the S7-300 have a system byte available? If so, where do I activate it?
2. If not, is there another easy way of getting hold of a "first scan" bit without building my own?
3. How do I get the system byte (if it exists) and the clock byte to show up in my tag table?
Thanks!