2.1.23.2 ACM Clock

The Analog Configuration multiplexer (ACM) clock defines the operating frequency of the ACM block, which resides within the analog block (AB) library macro. The ACM block contains the configuration registers for analog I/O and Real Time Counter (RTC) functionality.

The ACM port interface supports a maximum operating frequency of 10 MHz. This limit is a silicon requirement and must be observed whenever the ACM port interface is actively used.

If the ACM is configured during system initialization and the ACM port interface is not accessed during normal operation, the ACM clock may be driven at a frequency greater than 10 MHz. In this state, the ACM is inoperable, and any access attempts are invalid. During simulation, the AB library macro may report warning messages indicating that the ACM clock frequency exceeds 10 MHz; these warnings can be safely ignored as long as the ACM interface is not used while operating above the maximum supported frequency.