4.9.1. Register values

Figure 4.17 shows a register overview. Table 4.42 lists the DMC registers. The Typical value column describes values loaded by a version of Boot Monitor. For detailed register descriptions, see the PL340 Technical Reference Manual.


Refer to the application note for your baseboard and Core Tile combination for values for your system. The application note package contains a Boot Monitor that initializes the DDR registers after power up.

The platform.a library contains memory setup routines. See Building an application with the platform library.

Figure 4.17. DMC register overview

DMC register overview

Table 4.42. DMC register summary




Typical value





-Return DMC status


Write-only-Set DMC configuration
direct_cmd0x10018008Write-only-Pass commands to external memory
memory_cfg0x1001800CRead/Write0x00010020Set memory configuration
refresh_prd0x10018010Read/Write0x00000200Set refresh period
cas_latency0x10018014Read/Write0x00000006Set CAS latency
t_dqss0x10018018Read/Write0x00000001Set duration for write to DQS
t_mrd0x1001801CRead/Write0x00000002Set the mode register in the defined number of memory cycles
t_ras0x10018020Read/Write0x00000003Set RAS precharge delay
t_rc0x10018024Read/Write0x00000004Set the active bank delay
t_rcd0x10018028Read/Write0x00000007Set RAS to CAS minimum delay
t_rfc0x1001802CRead/Write0x000001F2Set autorefresh duration
t_rp0x10018030Read/Write0x00000015Set precharge to RAS delay
t_rrd0x10018034Read/Write0x00000002Set the active bank delay
t_wr0x10018038Read/Write0x00000003Set write to precharge delay
t_wtr0x1001803CRead/Write0x00000002Set write to read delay
t_xp0x10018040Read/Write0x00000001Set duration for exit power down command
t_xsr0x10018044Read/Write0x0000000ASet duration for exit self refresh
t_esr0x10018048Read/Write0x00000014Set duration for self refresh command
config0x10018100Read/Write0x00000000Set quality of service
chip_cfg00x10018200Read/Write0x0000FF00Set external memory configuration
reserved0x10018158- 0x10018FDC---
periph_id_n0x10018FE0- 0x10018FECRead-only-Contains peripheral ID
comp_id_n0x10018FF0- 0x10018FFCRead-only-Contains peripheral version

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