Mpu I/O Interrupts - Texas Instruments OMAP5910 Technical Reference Manual

7.3 MPU I/O
7.3.1

MPU I/O Interrupts

7.3.2 MPU I/O Clocks and Reset
The MPU I/O module enables direct I/O communications between the MPU
(through the public TIPB) and external devices (see Figure 7-10).
Two types of I/Os can be used:
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Specific I/Os dedicated for 8x8 keyboard connection:
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Eight inputs (KB R[7:0]) for row lines
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Eight outputs (KB.C[7:0]) for column lines
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General-purpose I/Os:
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Five MPU I/O signals (5, 4, 3, 2, and 1) are available in the default
OMAP5910 multiplexing.
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Five additional MPU I/O signals (12, 11, 7, 6, and 0) can be used by
configuring the OMAP5910 multiplexing. For more detail, see
Section 6.8 and Section A.2, I/O Functional Multiplexing.
The MPU I/O module generates two interrupts:
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The keyboard interrupt (KEYBOARD_INT), used to detect a key press,
connected to the MPU interrupt handler level2, line1 (edge-sensitive)
-
The GPIO interrupt (GPIOS_INT), used to detect an edge on one
MPUIO input, connected to the MPU interrupt handler level2, line5
(level-sensitive).
The MPU I/O module has two clocks:
-
The 32-kHz system clock (CLK_32KHZ), which comes, through the
ULPD, from either the OMAP5910 32-kHz oscillator or the OMAP5910
CLK32K_IN CMOS input. For more detail, see Chapter 15, Clock
Generation and System Reset Management).
-
The 12-MHz clock (FREE_RUN_CLK), used to resynchronize the
GPIO_INT register read. Comes from the MPU peripheral fixed clock
(XORCLK). This clock is free running when OMAP5910 is awake.
The MPU TIPB reset (MPU_PER_RESET) resets the MPU I/O module.
MPU Public Peripherals
MPU I/O
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