PmodSD

[BenBog]

I've seen you guys answer questions about the PmodSD IP and wondered if you could give me a quick answer. 

I am using the IP with microblaze and have the example working. 

I am trying to record data at 2.5Mbits/s. I have discovered that you can only write 512 bytes per fswrite. 

But I can't get faster than 1Mbits/s. 

I want to know if there is an easy way to speed up the write speed. Is this configurable?

I also see it as a possibility to switch to quad mode. But I don't see how to switch the IP to quad spi mode. 

 

Any help would be appreciated.

BEN

[jpeyron]

Hi @BenBog,

Welcome to the Digilent forums!

To use the Quad mode you would want to start with a fresh Quad SPI IP Core set to Quad mode and constrain the pmod port pins through and XDC.  Once you have generated a bitstream and have exported the hardware and launch SDK you should be able to use the libraries with some altering of the libraries to account for the change in the spi bus. Here is a forum thread that discussed using HDL to control the SD card that might be helpful as well.

best regards,

Jon

[BenBog]

Is there anyway to change the write speed of the IP?

 

BEN

[jpeyron]

Hi @BenBog,

I am not aware of a way to speed up the write speed of the IP. I would suggest looking at the Xilinx SPI drivers here: C:\Xilinx\SDK\2019.1\data\embeddedsw\XilinxProcessorIPLib\drivers\spi_v4_4 and the AXI Quad SPI v3.2LogiCORE IP Product Guide. 

best regards,

Jon