MCIMX31L FREESCALE [Freescale Semiconductor, Inc], MCIMX31L Datasheet - Page 15

• Manufacturer Part Number: MCIMX31L
• Description: Multimedia Applications Processors
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

2.3.16
The Keypad Port is designed to interface with keypad matrix with 2-contact or 3-point contact keys. The
Keypad Port is designed to simplify the software task of scanning a keypad matrix. With appropriate
software support, the KPP is capable of detecting, debouncing and decoding one or multiple keys pressed
simultaneously in the keypad. The KPP supports up to 8 x 8 external key pad matrix. Its port pins can be
used as general purpose I/O. Using an open drain design the KPP includes glitch suppression circuit
design, multiple keys, long key, and standby key detection.
2.3.17
The MPEG-4 encoder in the i.MX31 and i.MX31L accelerates video compression, in compliance with the
MPEG-4 standard. The encoder provides several levels of compression formats including MPEG-4 simple
profile (all levels) and H.263 baseline. The encoder can encode at a pixel rate up to VGA @ 30 fps and
compressed bit-rates up to 4 Mbps. The MPEG-4 encoder provides what is essentially the complete video
processing chain, generating a Huffman-coded stream with the exception of the formation of the final
MPEG-4 stream which is the only burden put on the ARM11 processor. Additional processing provided
by the MPEG-4 encoder includes picture smoothening (low-pass filter) and camera movement
stabilization. Support for enhanced conference call format in the form of additional information inserted
within the MPEG stream, used by a MPEG-4 decoder to improve performance.
2.3.18
The MSHC is located between the AIPS and the Sony Memory Stick and provides support for data
transfers between the i.MX31/i.MX31L and the Memory Stick (MS). The memory stick host controller
consists of two sub modules; the MSHC gasket and the Sony Memory Stick Host Controller (SMSC). The
SMSC module, which is the actual memory stick host controller, is compatible with Sony Memory Stick
Ver 1.x and Memory Stick PRO. The gasket connects the AIPS IP bus to the SMSC interface to allow
communication and data transfers via the IP Bus.
The MSHC gasket uses a reduced IP Bus interface that supports the IP bus read/write transfers that include
a back-to-back read or write {mshc_rd_wr_data,back_to_back_rw, back_to_back_complex}. DMA
transfers also take place via the IP Bus interface.{mshc_sdma}.
A transfer can be initiated by the SDMA or the host (through AIPS) in response to an MSHC DMA request
or interrupt. The SMSC has two SDMA address modes—a single address mode and a dual address mode.
The MSHC is set to dual address mode for transfers with the SDMA. In dual address mode, when the
MSHC requests a transfer with the DMA request (XDRQ), the SDMA will initiate a transfer to the MSHC.
Freescale Semiconductor
Keypad Port (KPP)
MPEG-4 Video Encoder (MPEG-4)
Memory Stick Host Controller (MSHC)
All details regarding the operation of the SMSC module can be found
separately in “Memory Stick/Memory Stick PRO Host Controller IP
Specification 1.3”.
i.MX31/i.MX31L Advance Information, Rev. 1.4
Preliminary
NOTE
Functional Description and Application Information
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