This video gives basic information on Using the UDC "UP Down Counter" instruction in the Do-more Designer software. It presents information that is commonly missed by users. This WILL NOT be a complete tutorial for the instruction but rather a supplement to the help file and customer experience.
This is a multi-scan instruction, and because it takes multiple scans to complete, it cannot be used in either Subroutines or Interrupt Service Routines. It can used in Programs and under special circumstances can also be used in Stages inside of a Program or in Tasks. See the help topic “Instruction Set Chart” for more information. This counter has 3 input rungs. One for both UP and One for down and down input. Both of these are edge triggered. This is indicated by the arrow on the input leg. The third input would be the Reset rung. When the reset is true, the counter will reset to zero. Notice that this counter has two preset one for up count and one for down count. When the count is equal or greater that the up preset, the .done bit will turn on. When the count is equal to or less than the down preset, the down DONE bit will turn on.