MC1323X_1 Datasheet, PDF (12/38 Pages) Freescale Semiconductor, Inc – Low Cost SoC Remote Control Platform for the 2.4 GHz IEEE® 802.15.4 Standard

7.3 System Protection
The MC1323x provides several vehicles to maintain security or a high level of system robustness:
• Watchdog computer operating properly (COP) reset with option to run from dedicated internal
clock source or bus clock
• Low-voltage warning and detection with reset or interrupt; selectable trip points
• Illegal opcode detection with reset
• FLASH block protection
8 MCU Peripherals
The MC1323x has a functional set of MCU peripherals focused for intended applications.
8.1 Parallel Input/Output (GPIO)
The MC1323x has four I/O ports that provide up to 31 general-purpose I/O signals and 1 output only
signal. Many of these pins are shared with on-chip peripherals such as timer systems, communication
ports, or keyboard interrupts. When these other modules are not controlling the port pins, they revert to
general-purpose I/O control. For each I/O pin, a port data bit provides access to input (read) and output
(write) data, a data direction bit controls the direction of the pin, and a pullup enable bit enables an internal
pullup device (provided the pin is configured as an input), and a slew rate control bit controls the rise and
fall times of the pins.Parallel I/O features include
Parallel I/O features include:
• A total of 32 general-purpose I/O pins in four ports (PTA2 is output only)
• Hysteresis input buffers
• Software-controlled pull-ups on each input pin
• Software-controlled slew rate output buffers
• Eight port A pins shared with 32.768 kHz oscillator, IRQ, IIC, and BKGD
• Eight port B pins shared with KBI1[7:0]
• Eight port C pins shared with KBI2[3:0] and SPI
• Eight port D pins shared with TPM0, TPM1, TPM2, TPM3, CMT (with 20mA drive), UART, and
32MOUT (reference frequency clock output)
8.2 Keyboard Interrupt Modules (KBI)
The MC1323x has two KBI modules; KBI1 shares eight Port A pins and KBI2 shares the lower four pins
of Port C. Any KBI pin can be enabled as a keyboard input that can act as an interrupt request. As a result,
the total 12 KBI inputs allows as large as a 12x12 keyboard matrix with use of other GPIO pins as outputs
to the matrix.
All enabled KBI inputs can be configured for edge-only sensitivity or edge-and-level sensitivity. They also
can be configured for either rising edge / high-level or falling-edge/low-level sensitivity. When enabled
MC1323x Advance Information, Rev. 0.0
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Freescale Semiconductor