NXP Semiconductors MC9S08QL4, Справочное руководство

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MC9S08QL8 MCU Series Reference Manual, Rev. 1
NXP Semiconductors 163
Chapter 12
Modulo Timer (S08MTIMV1)
12.1 Introduction
The MTIM is a simple 8-bit timer with several software selectable clock sources and a programmable
interrupt.
The central component of the MTIM is the 8-bit counter, which can operate as a free-running counter or a
modulo counter. A timer overflow interrupt can be enabled to generate periodic interrupts for time-based
software loops.
12.1.1 MTIM/TPM Configuration Information
The external clock for the MTIM module, TCLK, is selected by setting CLKS = 1:1 or 1:0 in MTIMCLK,
which selects the TCLK pin input. The TCLK input on PTA5 can be enabled as external clock inputs to
both the MTIM and TPM modules simultaneously.
12.1.2 MTIM Clock Gating
The bus clock to the MTIM can be gated on and off using the MTIM bit in SCGC1. This bit is set after any
reset, which enables the bus clock to this module. To conserve power, the MTIM bit can be cleared to
disable the clock to this module when not in use. See
Section 5.7, Peripheral Clock Gating for details.