• 32-bit counter resolution

• Clocked by bus clock frequency

• DMA support

4.5.5.3 Real-Time Clock (RTC)

• 32-bit seconds counter with 32-bit alarm

• 16-bit prescaler with compensation

• Register write protection

• Hard Lock requires MCU POR to enable write access

• Soft lock requires system reset to enable write/read access

Communication Interfaces

• Up to 100 kbps with maximum bus loading

• Multi-master operation

• Software programmable for one of 64 different serial clock frequencies

• Programmable slave address and glitch input filter

• Interrupt or DMA driven byte-by-byte data transfer

• Arbitration lost interrupt with automatic mode switching from master to slave

• Calling address identification interrupt

• Bus busy detection broadcast and 10-bit address extension

• Address matching causes wake-up when processor is in low power mode

4.5.6.2 USB On-The-Go Module (FS/LS)

• Complies with USB specification rev 2.0

• USB host mode

• Supports enhanced-host-controller interface (EHCI)

• Allows direct connection of FS/LS devices without an OHCI/UHCI companion controller

• Supported by Linux and other commercially available operating systems

• USB device mode

• Full-speed operation via the on-chip transceiver

• Supports one upstream facing port

• Supports four programmable, bidirectional USB endpoints, including endpoint 0

• Suspend mode/low power

• As host, firmware can suspend individual devices or the entire USB and disable chip clocks for low-power

operation

• Device supports low-power suspend

• Remote wake-up supported for host and device

• Integrated with the processor’s low power modes

• Includes an on-chip full-speed (12 Mbps) and low-speed (1.5 Mbps) transceiver

4.5.6.3 USB Voltage Regulator

• 5 V regulator input typically provided by USB VBUS power

• 3.3V regulated output powers on-chip USB transceiver

• Output pin from regulator can be used to power external board components and source up to 120mA

• Eliminates cost of external LDO

• 3.3V regulated output can power MCU main power supply

4.5.6

Communication Interfaces

KL24/KL25 Product Brief, Rev. 2, 6/2012

16

Preliminary

Freescale Semiconductor, Inc.

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