MCF52223 FREESCALE [Freescale Semiconductor, Inc], MCF52223 Datasheet - Page 13

• Manufacturer Part Number: MCF52223
• Description: Microcontroller Data Sheet
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

with software-selectable duty rates from 0% to 100%. The PWM outputs have programmable polarity, and
can be programmed as left aligned outputs or center aligned outputs. For higher period and duty cycle
resolution, each pair of adjacent channels ([7:6], [5:4], [3:2], and [1:0]) can be concatenated to form a
single 16-bit channel. The module can thus be configured to support 8/0, 6/1, 4/2, 2/3, or 0/4 8-/16-bit
channels.
1.2.16 Software Watchdog Timer
The watchdog timer is a 32-bit timer that facilitates recovery from runaway code. The watchdog counter
is a free-running down-counter that generates a reset on underflow. To prevent a reset, software must
periodically restart the countdown.
1.2.17 Phase Locked Loop (PLL)
The clock module contains a crystal oscillator, 8 MHz on-chip relaxation oscillator (OCO), phase-locked
loop (PLL), reduced frequency divider (RFD), low-power divider status/control registers, and control
logic. In order to improve noise immunity, the PLL, crystal oscillator, and relaxation oscillator have their
own power supply inputs: VDDPLL and VSSPLL. All other circuits are powered by the normal supply
pins, VDD and VSS.
1.2.18 Interrupt Controller (INTC)
The MCF52223 has a single interrupt controller that supports up to 63 interrupt sources. There are 56
programmable sources, 49 of which are assigned to unique peripheral interrupt requests. The remaining 7
sources are unassigned and may be used for software interrupt requests.
1.2.19 DMA Controller
The direct memory access (DMA) controller provides an efficient way to move blocks of data with
minimal processor intervention. It has four channels that allow byte, word, longword, or 16-byte burst line
transfers. These transfers are triggered by software explicitly setting a DCRn[START] bit or by the
occurrence of certain UART or DMA timer events.
1.2.20 Reset
The reset controller determines the source of reset, asserts the appropriate reset signals to the system, and
keeps track of what caused the last reset. There are seven sources of reset:
Freescale Semiconductor
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External reset input
Power-on reset (POR)
Watchdog timer
Phase locked-loop (PLL) loss of lock
PLL loss of clock
Software
MCF52223 ColdFire® Microcontroller Data Sheet, Rev. 1
Preliminary
MCF52223 Family Configurations
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