Motorola TMS320C6711D Emif big endian mode correctness, Emif Data Lines Pins Where Data Present

Models: TMS320C6711D

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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 8-bit and 16-bit data on the ED[7:0] side of the bus if using Little Endian mode (HD8 = 1) and to the ED[31:24] side of the bus if using Big Endian mode. Figure 14 shows the mapping of 16-bit and 8-bit devices with EMIF endianness correction.

EMIF DATA LINES (PINS) WHERE DATA PRESENT

ED[31:24] (BE3)

ED[23:16] (BE2)

ED[15:8] (BE1)

ED[7:0] (BE0)

32-Bit Device in Any Endianness Mode

16-Bit Device in Big Endianness Mode

16-Bit Device in Little Endianness Mode

 

 

 

 

8-Bit Device in Big

 

 

8-Bit Device in Little Endianness Mode

Endianness Mode

 

 

 

 

 

Figure 14. 16/8-Bit EMIF Big Endian Mode Correctness Mapping (HD12 = 1)

When HD12 = 0, enabling EMIF endianness correction, the EMIF will present 8-bit and 16-bit data on the ED[7:0] side of the bus, regardless of the endianess mode (see Figure 15).

EMIF DATA LINES (PINS) WHERE DATA PRESENT

ED[31:24] (BE3)

ED[23:16] (BE2)

ED[15:8] (BE1)

ED[7:0] (BE0)

32-Bit Device in Any Endianness Mode

16-Bit Device in Any Endianness Mode

8-Bit Device in Any Endianness Mode

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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Motorola TMS320C6711D warranty Emif big endian mode correctness, Emif Data Lines Pins Where Data Present