2.6.3. Miscellaneous signals

You can use the following signals as general-purpose control signals for logic external to the SMC:

smc_user_config[7:0]

General purpose output ports that are driven directly from the write-only APB register. If you do not require these ports leave them unconnected. See also the SMC User Configuration Register at 0x1204.

smc_user_status[7:0]

General purpose input ports that are readable from the APB interface through the smc_user_status Register. If you do not require these ports then tie them either HIGH or LOW. These ports are connected directly to the APB interface block. Therefore, if they are driven from external logic that is not clocked by the SMC smc_aclk signal, then you require external synchronization registers. See also the SMC User Status Register at 0x1200.

You can use the following miscellaneous signals as tie-offs to change the operational behavior of the SMC:

smc_a_gt_m0_sync

When HIGH, indicates that smc_aclk is greater than and synchronous to smc_mclk0.

smc_async0

When HIGH, indicates smc_aclk is synchronous to smc_mclk0. Otherwise they are asynchronous. Ensure that smc_async0 is tied to the same value as smc_msync0.

smc_dft_en_clk_out

Use this signal for Automatic Test Pattern Generator (ATPG) testing only. Tie it LOW for normal operation.

smc_msync0

When HIGH, indicates smc_mclk0 is synchronous to smc_aclk. Otherwise they are asynchronous. Ensure that smc_msync0 is tied to the same value as smc_async0.

smc_rst_bypass

Use this signal for ATPG testing only. Tie it LOW for normal operation.

smc_use_ebi

When HIGH, indicates that the SMC must operate with a PrimeCell EBI. See the ARM PrimeCell External Bus Interface (PL220) Technical Reference Manual.

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