MCIMX27_08 Datasheet, PDF (18/132 Pages) Freescale Semiconductor, Inc – Multimedia Applications Processor

Functional Description and Application Information
— Passive color panel:
– 4 (mapped to RGB444) / 8 (mapped to RGB444) / 12 (RGB444) bits per pixel (bpp)
— TFT panel:
– 4 (mapped to RGB666) / 8 (mapped to RGB666) / 12 (RGB444) / 16 (RGB565) / 18
(RGB666) bpp
— 16 and 256 colors out of a palette of 4096 colors for 4 bpp and 8 bpp CSTN display,
respectively
— 16 and 256 colors out of a palette of 256 colors for 4 bpp and 8 bpp TFT display, respectively
— True 4096 colors for a 12 bpp display
— True 64K colors for 16 bpp
— True 256K colors for 18 bpp
— 16-bit AUO TFT LCD Panel
— 24-bit AUO TFT LCD Panel
2.3.21 Multi-Master Memory Interface (M3IF)/M3IF-ESDCTL/MDDRC
Interface
The M3IF-ESDCTL/MDDRC interface is optimized and designed to reduce access latency by generating
multiple accesses through the dedicated ESDCTL/MDDRC arbitration (MAB) module, which controls the
access to and from the Enhanced SDRAM/MDDR memory controller. For the other port interfaces, the
M3IF only arbitrates and forwards the master requests received through the Master Port Gasket (MPG)
interface and M3IF Arbitration (M3A) module toward the respective memory controller. The masters that
interface with the M3IF include the ARM Platform, FEC, LCDC, H.264, and the USB. The controllers are
the ESDCTL/MDDRC, PCMCIA, NFC, and WEIM.
2.3.22 Multi-Layer AHB Crossbar Switch (MAX)
The ARM926EJ-S processor’s instruction and data buses—and all alternate bus master
interfaces—arbitrate for resources via a 6 × 34 Multi-Layer AHB Crossbar Switch (MAX). There are six
(M0–M5) fully functional master ports and three (S0–S2) fully functional slave ports. The MAX is
uni-directional. All master and slave ports are AHB-Lite compliant.
The design of the crossbar switch enables concurrent transactions to proceed from any master port to any
slave port. That is, it is possible for all three slave ports to be active at the same time as a result of three
independent master requests. If a particular slave port is simultaneously requested by more than one master
port, arbitration logic exists inside the crossbar to allow the higher priority master port to be granted the
bus, while stalling the other requestor(s) until that transaction has completed. The slave port arbitration
schemes supported are fixed, programmable fixed, programmable default input port parking, and a round
robin arbitration scheme.
The Crossbar Switch also monitors the ccm_br input (clock control module bus request), which requests
a bus grant from all four slave ports. The priority of ccm_br is programmable and defaults to the highest
priority. Upon receiving bus grants for all four output ports, the ccm_bg output will assert. At this point,
the clock control and reset module (CRM) can turn off hclk and be assured there are no outstanding AHB
i.MX27 and i.MX27L Data Sheet, Rev. 1.2
18
Freescale Semiconductor
Preliminary—Subject to Change Without Notice