9 CREATING A HARDWARE LOGIC
9.2 Multi Function Counter Block
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Monitor
The following table shows the monitors of the counter timer block.
*1 Even when no "User Address" is assigned, an overflow and an underflow are detected and the multi function counter block overflow
error (error code: 100H) and the multi function counter block underflow error (error code: 101H) occur. These errors are detected
only when the linear counter mode is set for 32-bit counter timer blocks.
The following table shows "User Address" used for the monitors.
Variable name Data type Description
Count Value Word A count value is stored in the buffer memory area specified with "User Address".
Latch Value Word A latched count value is stored in the buffer memory area specified with "User Address".
Overflow Word When an overflow is detected, 1 is stored in the buffer memory address specified with "User Address".
*1
Underflow Word When an underflow is detected, 1 is stored in the buffer memory address specified with "User Address".
*1
Variable name Data type Linkable block Valid range Description
User Address Word 1000 to 1099 Only even addresses can be assigned to monitors of
two words (32 bits).