asmith@terrasonde.com (bitsrflyin) wrote in 
news:79af1a54.0312250958.6b7db6d7@posting.google.com:

> Has anyone used one of the SPORTs on an ADSP-2185 as an SPI port? I am
> trying to interface with an SD card using SPI mode. Really I just need
> to read data from the SD card. I have all of the SD specs, but I am
> unsure about getting the SPORT to function as an SPI port.
> 
> Any ideas would be greatly appreciated.
> 
> Andrew Smith
> 

You can use a SPORT as an SPI port. If the DSP is the SPI master, you can 
use two NOR gates, such as half a 74VHC02.

Here's the recipe:

Connect one NOR as an inverter to create /SCLK. This creates a small 
delay from SCLK so don't skip this step.

The input of the first NOR (/SCLK) feeds one input of the 2nd NOR. The 
other input connects to RFS & TFS (connected together). The output of the 
2nd NOR is the SPI_CLK gated clock. DT and DR are MOSI & MISO. Use a FLAG 
pin if you want an SPI CS.

This is the method we use in our DSP-8300 small module (ADSP-2186 based)
to communicate with a PIC processor.  

-- 
Al Clark
Danville Signal Processing, Inc.
--------------------------------------------------------------------
Purveyors of Fine DSP Hardware and other Cool Stuff
Available at http://www.danvillesignal.com

Has anyone used one of the SPORTs on an ADSP-2185 as an SPI port? I am
trying to interface with an SD card using SPI mode. Really I just need
to read data from the SD card. I have all of the SD specs, but I am
unsure about getting the SPORT to function as an SPI port.

Any ideas would be greatly appreciated.

Andrew Smith