Anybody see anything wrong with this design?
5V and 3.3V come from regulators with 10uf/100nF on input pins and 100nF on the output pins.
R28 is 10k.
Signals are coming from/going to an AT1284.
Should be just like this one.http://www.ladyada.net/make/logshield/design.html
The shield works, the embedded design does not. They use seperate SS pins, so no conflict there.
"The SD card socket on board does not work. I
spent some time just now with my volt meter tracing stuff. I also verified
the correct pin use on the SD socket. Everything is as it should be, but I
have no way to verify voltage at the output pin of the SD. And, the error
I get is a read error.
The voltage out of the level shifter on SD card PIN 5 is 3.84 and it is
properly connected (through the level shifter) to the CPU. Same with SS
and MOSI. I also verified 3.84V on the VDD pins and a good ground on the
I noticed that the SD card data out pin (MISO) does not go through the
level shifter, but directly to the CPU.
I also noted that my SD card shield works perfectly on this board, so SPI
itself is working and so is the test software that talks to the SD card."