Spectrum Digital TMS320DM365, Technical Reference

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Spectrum Digital, Inc
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2.1 Asynchronous EMIF Interface
An asynchronous 16 bit EMIF with two chip enables divide up the address space and
allow for asynchronous accesses on the EVM. This interface connects to the NAND,
One NAND, and CPLD registers on the EVM board.
2.1.1 NAND Flash
The DM365 has 2 gigabytes of NAND Flash memory mapped into the CE0 space. The
NAND Flash memory is used primarily for boot loading and file system on the DM365
EVM. The CE0 selects the device and needs to be configured to 8 bits wide when
accessing the NAND.
Switch SW5, position 1 (OFF) selects CE0 mapped to NAND. The NAND and One
NAND interface share the same CE0 chip select so only 1 device can be operational at
any given time.
When the NAND flash interface is selected the spare address lines can be used by the
internal DM365 key pad interface. This interface is enabled by setting a control bit in
the CPLD to enable the on board CBTLV switches to the keypad matrix.
2.1.1.1 One NAND
The EVM supports 128 Megabytes of One NAND. This interface is 16 bits wide and
CE0 must be configured for 16 bit wide operation when using One NAND. Switch SW5,
position 1 (ON) selects the One NAND device. When the One NAND is selected the on
board NAND is not available. Since the One NAND uses all the asynchronous
EMIF address lines the on-chip key pad controller on the DM365 cannot be used when
the One NAND is selected.