Samsung S3C6400X User Manual page 111

S3C6400X RISC MICROPROCESSOR
command.
Program mem_cmd in direct_cmd to '2'b11', which makes DRAM Controller issue 'Autorefresh' memory
command.
Program mem_cmd in direct_cmd to '2'b00', which makes DRAM Controller issue 'Prechargeall' memory
command.
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
DRAM CONTROLLER
5-5