SDRAM Controller Write Cycle

The SDRAMC allows burst access or single access. In both cases, the SDRAMC keeps track of the active row in each bank, thus maximizing performance. To initiate a burst access, the SDRAMC uses the transfer type signal provided by the master requesting the access. If the next access is a sequential write access, writing to the SDRAM device is carried out. If the next access is a write-sequential access, but the current access is to a boundary page, or if the next access is in another row, then the SDRAMC generates a precharge command, activates the new row and initiates a write command. To comply with SDRAM timing parameters, additional clock cycles are inserted between precharge and active commands (tRP), and between active and write commands (tRCD). For definition of these timing parameters, refer to the SDRAMC Configuration Register. Refer to the following figure.

Figure 1. Write Burst SDRAM Access