
Functional Overview
172
December 2003 Revised March 2005
SPRS231D
Built-in 64-byte FIFO for buffered read or write
16-bit-wide access bus to maximize bus throughput
Designed for low power
Wide interrupt capability
Programmable clock generation
Two DMA channels
NOTE:
The MMC/SDIO1 interface includes all the MMC/SDIO pins except the direction controls (data
and control).
3.6.10
MPUIO Interface
The MPUIO feature allows communication with an external device through as many as 16 MPUIOs. These
MPUIOs can be configured on a pin-by-pin basis as inputs or outputs. When configured as input, each MPUIO
can be individually selected to generate interrupts on a level change (rising or falling edge). In normal
operation, the MPUIO inputs are latched at the falling edge of 32 kHz. In event capture mode, one of the
MPUIO inputs can be assigned a clock source, and all the other inputs are latched on its falling edge.
The MPUIO module functional clock domain is clocked by the OMAP5912 32-kHz clock. This clock is always
fed into the block, regardless of the state of the chip (awake, asleep, or idle). This allows external event latching
and interrupt generation even when the system is in idle mode, to wake up the system via interrupt.
The MPUIO module interfaces with the host through a TIPB bus. The MPU peripheral clock resynchronizes
register access to the module and avoids time-out on the TIPB bus caused by the functional clock being too
slow.
3.6.11
LED Pulse Generators (LPG)
There are two separate LED pulse generator (LPG) modules. Each LPG module provides an output for an
indication LED. The blinking period is programmable between 152 ms and 4 s or the LED can be switched
on or off permanently.
3.6.12
Frame Adjustment Counter (FAC)
The frame adjustment counter (FAC) is a simple peripheral that counts the number of rising edges of one signal
(start of frame interrupt of the USB function) during a programmable number of rising edges of a second signal
(transmit frame synchronization of McBSP2). The FAC may only be used with these specific USB Function
and McBSP2 signals. The count value can be used by system-level software to adjust the duration of the two
time domains with respect to each other to reduce overflow and underflow. If the data being transferred is audio
data, this module can be part of a solution that reduces pops and clicks. The FAC module generates one
second-level interrupt to the MPU.