NXP Semiconductors freescale K51 Series Reference Manual

24.3.8 MCG Auto Trim Control Register (MCG_ATC)Address: MCG_ATC is 4006_4000h base + 8h offset = 4006_4008hBit 7 6 5 4 3 2 1 0Read ATME ATMS ATMF 0WriteReset 0 0 0 0 0 0 0 0MCG_ATC field descriptionsField Description7ATMEAutomatic Trim Machine EnableEnables the Auto Trim Machine to start automatically trimming the selected Internal Reference Clock.NOTE: ATME deasserts after the Auto Trim Machine has completed trimming all trim bits of the IRCSclock selected by the ATMS bit.Writing to C1, C3, C4, and ATC registers or entering Stop mode aborts the auto trim operation and clearsthis bit.0 Auto Trim Machine disabled.1 Auto Trim Machine enabled.6ATMSAutomatic Trim Machine SelectSelects the IRCS clock for Auto Trim Test.0 32 kHz Internal Reference Clock selected.1 4 MHz Internal Reference Clock selected.5ATMFAutomatic Trim machine Fail FlagFail flag for the Automatic Trim Machine (ATM). This bit asserts when the Automatic Trim Machine isenabled (ATME=1) and a write to the C1, C3, C4, and ATC registers is detected or the MCG enters intoany Stop mode. A write to ATMF clears the flag.0 Automatic Trim Machine completed normally.1 Automatic Trim Machine failed.4–0ReservedThis read-only field is reserved and always has the value zero.24.3.9 MCG Auto Trim Compare Value High Register (MCG_ATCVH)Address: MCG_ATCVH is 4006_4000h base + Ah offset = 4006_400AhBit 7 6 5 4 3 2 1 0Read ATCVHWriteReset 0 0 0 0 0 0 0 0Chapter 24 Multipurpose Clock Generator (MCG)K51 Sub-Family Reference Manual, Rev. 6, Nov 2011Freescale Semiconductor, Inc. 539