Allen-Bradley MicroLogix 1200 Reference Manual page 73

The HSC is extremely versatile; the user can select or configure each HSC
for any one of eight (8) modes of operation. (Operating Modes are
discussed later in this chapter. See section HSC Mode (MOD) on page
5-16). Some of the enhanced capabilities of the High-Speed Counters are:
• 20 kHz operation
• High-speed direct control of outputs
• 32-bit signed integer data (count range of ± 2,147,483,647)
• Programmable High and Low presets, and Overflow and Underflow
setpoints
• Automatic Interrupt processing based on accumulated count
• Run-time editable parameters (from the user control program)
The High-Speed Counter function operates as described in the following
diagram.
Overflow
High Preset
0
Low Preset
Underflow
Using the High-Speed Counter
+2,147,483,647 maximum
-2,147,483,648 minimum
Publication 1762-RM001C-EN-P
5-3