11.6.2 High-frequency input
Terminals: C1-C4, U1-U12
Resistance: Configurable in terminal pairs with 100 kΩ pull-up or pull-down
Typical Wave Form: 5 or 3.3 VDC square wave
Maximum Input Frequency: 1 MHz
11.6.3 Low-level AC input
Terminals: U2, U4, U6, U8, U10, U12
NOTE:
When an even numbered U terminal (for example, U2) is used for low-level AC pulse
counting, its paired odd numbered terminal (U1 in this example) can be used only for switch-
closure or high-frequency pulse counting or in the digital I/O control or state function.
DC-offset rejection: Internal AC coupling eliminates DC-offset voltages up to ±0.05 VDC
Input Hysteresis: 12 mV at 1 Hz
Low-Level AC Pulse Input Ranges for U Terminals:
Sine wave (mV RMS) Range (Hz)
20
1.0 to 20
200
0.5 to 200
2000
0.3 to 10,000
5000
0.3 to 20,000
11.7 Digital input/output specifications
Terminals configurable for digital input and output (I/O) including status high/low, pulse width
modulation, external interrupt, edge timing, switch closure pulse counting, high-frequency pulse
counting, UART, RS-232, RS-485, SDM, SDI-12, I2C, and SPI function. Terminals are configurable
in pairs for 5 V or 3.3 V logic for some functions.
11. CR6 Specifications
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