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Since the value of the W_SETUP/R_SETUP, W_STROBE/R_STROBE, W_HOLD/R_HOLD, and TA fields are equal to EMIF clock cycles minus 1 cycle, the A1CR should be configured as in Table 30. In this example, although the EM_WAIT signal is connected to the R/B signal of the NAND Flash the Extended Wait mode of the EMIF is not used, therefore the asynchronous wait cycle configuration register (AWCCR) does not need to be programmed.
| Table 30. Configuring A1CR for HY27UA081G1M Example | |
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Parameter | Setting | |
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SS | Select Strobe mode. | |
| • SS = 0. Places EMIF in Normal Mode. | |
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EW | Extended Wait mode enable. | |
| • EW = 0. Disabled Extended wait mode. | |
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W_SETUP/R_SETUP | Read/Write setup widths. | |
| • | W_SETUP = 0 |
| • | R_SETUP = 2 |
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W_STROBE/R_STROBE | Read/Write strobe widths. | |
| • | W_STROBE = 6 |
| • | R_STROBE = 7 |
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W_HOLD/R_HOLD | Read/Write hold widths. | |
| • | W_HOLD = 1 |
| • | R_HOLD = 0 |
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TA | Minimum turnaround time. | |
| • | TA = 2 |
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ASIZE | Asynchronous device bus width. | |
| • ASIZE = 0, select an | |
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Since this is a NAND Flash example, the EMIF must be configured for NAND Flash mode. This is accomplished by configuring the NAND Flash control register (NANDFCR) as in Table 31. In NANDFCR, chip select space 2 must be configured with NAND Flash mode enabled.
| Table 31. Configuring NANDFCR for HY27UA081G1M Example |
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Parameter | Setting |
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CS5ECC | NAND Flash ECC start for chip select 5. |
| • CS5ECC = 0. Not set during configuration. Only set just prior to reading or writing data. |
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CS4ECC | NAND Flash ECC start for chip select 4. |
| • CS4ECC = 0. Not set during configuration. Only set just prior to reading or writing data. |
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CS3ECC | NAND Flash ECC start for chip select 3. |
| • CS3ECC = 0. Not set during configuration. Only set just prior to reading or writing data. |
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CS2ECC | NAND Flash ECC start for chip select 2. |
| • CS2ECC = 0. Not set during configuration. Only set just prior to reading or writing data. |
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CS5NAND | NAND Flash mode for chip select 5. |
| • CS5NAND = 0. NAND Flash mode is disabled. |
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CS4NAND | NAND Flash mode for chip select 4. |
| • CS4NAND = 0. NAND Flash mode is disabled. |
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CS3NAND | NAND Flash mode for chip select 3. |
| • CS3NAND = 0. NAND Flash mode is disabled. |
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CS2NAND | NAND Flash mode for chip select 2. |
| • CS5NAND = 1. NAND Flash mode is enabled. |
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SPRUEQ7C | Asynchronous External Memory Interface (EMIF) 47 |
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