SPRS292A − OCTOBER 2005 − REVISED NOVEMBER 2005
EMIF big endian mode correctness
The HD8 pin device endian mode (LENDIAN) selects the endian mode of operation (Little or Big Endian). For the device, Little Endian is the default setting.
The HD12 pin (EMIF Big Endian Mode Correctness) [EMIFBE] enhancement allows the flexibility to change the EMIF data placement on the EMIF bus.
When using the default setting of HD12 = 1, the EMIF will present
EMIF DATA LINES (PINS) WHERE DATA PRESENT
ED[31:24] (BE3)
ED[23:16] (BE2)
ED[15:8] (BE1)
ED[7:0] (BE0)
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Endianness Mode |
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Figure 14. 16/8-Bit EMIF Big Endian Mode Correctness Mapping (HD12 = 1)
When HD12 = 0, enabling EMIF endianness correction, the EMIF will present
EMIF DATA LINES (PINS) WHERE DATA PRESENT
ED[31:24] (BE3)
ED[23:16] (BE2)
ED[15:8] (BE1)
ED[7:0] (BE0)
Figure 15. 16/8-Bit EMIF Big Endian Mode Correctness Mapping (HD12 = 0)
This new endianness correction functionality does not affect systems using the default value of HD12=1.
This new feature does not affect systems operating in Little Endian mode.
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