Sdio

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LuisHS

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Hello.

I need add SDIO support to my development. I have download and install the SDFAT library and open the example TeensySdioDemo, compile and load to Teensy 3.6.

Now I run, and select option 1 for SdFatSdioEX, this work perfect, I check results in the Arduino Monitor Serie and there is a file in the SD card. These are data in Monitor;

size,write,read
bytes,KB/sec,KB/sec
512,16733.97,18772.84
1024,17299.63,18907.91
2048,16544.37,19059.21
4096,17457.50,19161.74
8192,17373.19,19207.90
16384,17273.20,19231.19
32768,17166.38,19241.91

totalMicros 6508199
yieldMicros 209248
yieldCalls 180
yieldMaxUsec 1433
kHzSdClk 45000
Done


But when I choose option 2 for SdFatSdio, this do not work, in the Monitor Serie windows, only see following text and there is not file in SD card:

size,write,read
bytes,KB/sec,KB/sec
512,


Somebody know why fail SdFatSdio option ??.
Its better and faster SdFatSdio than SdFatSdioEX ??

Seem that SdFatSdio work with DMA, so I understand that must to be faster than SdFatSdioEX. So if it's true, I prefer SdFatSdio, but in my current test this fail.

Kind Regards
 
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Its better and faster SdFatSdio than SdFatSdioEX ??
No, it's not. In fact, it's quite a bit slower for small blocks, e.g.:
https://forum.pjrc.com/threads/40150-CAN-logger-and-SD-card-speed

While the benchmark works for me, I've had issues with SdFatSdio working reliably.

There is little reason to use SdFatSdio. The SdFatSdioEX data transfer to the SD card runs at 20MByte/s, so the benefit from potentially running the SdFatSdio DMA transfer in the background is small.
 
No, it's not. In fact, it's quite a bit slower for small blocks, e.g.:
https://forum.pjrc.com/threads/40150-CAN-logger-and-SD-card-speed

While the benchmark works for me, I've had issues with SdFatSdio working reliably.

There is little reason to use SdFatSdio. The SdFatSdioEX data transfer to the SD card runs at 20MByte/s, so the benefit from potentially running the SdFatSdio DMA transfer in the background is small.


OK, thanks.
And do you know why fail by SdFatSdio ??, I have compile the original sketch without any modification, connect to Teensy 3.6 and only work with SdFatSdioEX.
 
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