Reading Data from DRAM - 64 Bit Memory Interface
- Updated2025-01-23
- 2 minute(s) read
Reading Data from DRAM - 64 Bit Memory Interface
Complete the following steps to read data from DRAM.
LabVIEW contains example VIs that read and write to the Random Access - 64 Bit memory interface. To access the NI Example Finder, open LabVIEW and select , then select . You can also access device-specific examples by selecting Add device from the Hardware pull-down menu in the NI Example Finder.
Note The Random Access - 64 Bit memory interface queues read requests internally.
Therefore, you may issue multiple read requests for different addresses before you
even receive the data back for your first read request. As a result, if you are
queuing up multiple read requests, it is important that you properly track the order
of the data that is returned when Read_Strobe asserts. All data returned from the
Random Access - 64 Bit memory interface when Read_Strobe asserts is properly ordered
with respect to the original read request command ordering.
- Ensure that the Command_FIFO_Full Boolean is FALSE.
- Drive the Address signal with the DRAM memory address that you want to read from.
- Drive the Command signal with 1. This signal communicates to the Random Access - 64 Bit memory interface to perform a memory read command.
- Drive the Command_Write_Enable signal to TRUE for one clock cycle. You must only drive this signal for a single clock cycle if you want to only issue a single memory read command. Each clock cycle in which this signal is asserted causes a new read command to be issued to the Random Access - 64 Bit memory interface.
- Continually monitor the state of the Read_Strobe signal. When this signal reads as TRUE, latch the 64-bit data value on the Read_Data_Upper and Read_Data_Lower signals. This contains the data most recently read from the Random Access - 64 Bit memory interface.