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Primary Timing
CAS# Latency (tCL)
The time between sending a column address to the memory and the beginning of the data
in response.
RAS# to CAS# Delay and Row Precharge (tRCDtRP)
RAS# to CAS# Delay : The number of clock cycles required between the opening of a row
of memory and accessing columns within it.
Row Precharge: The number of clock cycles required between the issuing of the precharge
command and opening the next row.
RAS# Active Time (tRAS)
The number of clock cycles required between a bank active command and issuing the
precharge command.
Command Rate (CR)
The delay between when a memory chip is selected and when the first active command can
be issued.
Secondary Timing
Write Recovery Time (tWR)
The amount of delay that must elapse after the completion of a valid write operation,
before an active bank can be precharged.
Refresh Cycle Time (tRFC)
The number of clocks from a Refresh command until the first Activate command to
the same rank.
RAS to RAS Delay (tRRD_L)
The number of clocks between two rows activated in different banks of the same
rank.
RAS to RAS Delay (tRRD_S)
The number of clocks between two rows activated in different banks of the same
rank.
Write to Read Delay (tWTR_L)
The number of clocks between the last valid write operation and the next read command to
the same internal bank.
